[Caves]

(A pair of potholers climb down a metal 'rope' ladder into a large cave with extraordinary stalagmites.)
SPENCER: Well, this is fantastic!
(Something roars in the distance.)
SPENCER: What was that?
DAVIS: Nothing.
(They move off. The young man, Spencer tries to take the lead.)
DAVIS: Wait.
(Davis leads off down a tunnel. There is another gurgling roar, closer now. Davis goes through a gap to confront - )
DAVIS: Spencer!
(Something very tall with big teeth, looking rather amphibian. It attacks Davis.)
DAVIS: Spencer!
(Spencer finds Davis' body and runs in terror.)

[UNIT garage workshop]

(The Doctor is happy in his work underneath a bright yellow 1930s style car, registration WHO 1.)
DOCTOR: (singing.) 'Twas brillig, and the slithy toves, Did gyre and gimble in the wabe
LIZ [OC]: Doctor?
DOCTOR: Come on, Bessie, be more co-operative. All mimsy were the borogroves, And the mome raths
LIZ: Doctor.
DOCTOR: Outgrabe. Oh, hello, Liz.
LIZ: You'll never get that thing running.
DOCTOR: Oh, don't you be so disrespectful. I'll have you know this is a car of great character. I was very lucky to get her.
LIZ: Are you really going to drive about in it?
DOCTOR: Yes, certainly. I've nearly finished my modifications. I thought we'd take her out for a trial run in a minute.
(He looks at a steel hoop.)
DOCTOR: Now I wonder what that's for. Oh, well.
LIZ: Urgent message from the Brigadier.
DOCTOR: Oh he's away, isn't he, investigating some scientists?
LIZ: Yes, well, he wants us to join him. 'Miss Shaw and the Doctor will report themselves forthwith to Wenley Moor. Attend a briefing meeting at precisely
DOCTOR: My dear Miss Shaw, I never report myself anywhere. Particularly not forthwith.
LIZ: Oh, it's just his way of putting things.
DOCTOR: No, I'm sorry, Liz. I won't go. I'm far too busy.
LIZ: Come on, Doctor.
DOCTOR: Twee. Twas brillig, and the slithy toves
LIZ: It would make a nice a nice trip for us. We could visit the caves.
DOCTOR: Caves? What caves?
LIZ: Well, that part of the country's famous for them.
DOCTOR: Oh. Is it?
LIZ: It is.
DOCTOR: Oh, all right then. I'll drive you up there in Bessie.
LIZ: Bessie?
DOCTOR: There, Bessie.
(The car.)
LIZ: I see.
(The Doctor plants a kiss on Bessie's radiator and the engine starts.)
DOCTOR: Well, there we are. Here, hold that, Liz, will you?
(The Doctor drives Liz through town streets carefully, and along unmade country tracks at high speed until they reach a Research facility in the middle of a moor. Okay, it is actually the Hogs Back radio transmitter site near Guildford, but so what?)

[Conference room]

(A briefing is being given to a room full of white coated scientists, with slides projected onto a screen at the back of the small stage.)
LAWRENCE: I trust that point is clear. And I would emphasise again that despite the presence of our friends from UNIT, to whom we shall give every possible co-operation, this problem is, I am sure, a scientific one.
(A UNIT soldier enters and whispers to the Brigadier.)
LAWRENCE: It is our duty as scientists to deal with it ourselves. Only by exercising redoubled vigilance in all our duties can we track down the errors that are holding back the work of this research centre.
(The soldier and the Brigadier leave.)

[Corridor]

LAWRENCE [OC]: The work of this research centre is vitally

[Research Centre reception]

BRIGADIER: Ah, there you are at last.
DOCTOR: There you are at last.
BRIGADIER: Right.
(The soldier leaves and a security officer gives Liz her papers back.)
DOCTOR: And just where are we?
BRIGADIER: In a cave.
LIZ: We can see that.
BRIGADIER: Or rather in an atomic research centre which has been built into these caves.
DOCTOR: Why? More security?
BRIGADIER: Exactly.
DOCTOR: Look, may I ask you, why am I here?
BRIGADIER: Come this way, will you? The meeting's waiting.

[Conference room]

LAWRENCE: We are already very considerably behind in our research programme, and I am deter
(The Brigadier, Liz and the Doctor enter.)
LAWRENCE: And I am determined we shall recover our lost ground, and go on to make the new and important discoveries that lie ahead. All right, that will be all.
(The scientists leave and three men in suits stay behind. Quinn bumps into a woman.)
QUINN: Oh, I'm sorry.
(Everyone say Hi! to Fulton MacKay.)
BRIGADIER: Gentlemen, my colleagues, Miss Elizabeth Shaw and the Doctor. Doctor Lawrence, director of this establishment.
LAWRENCE: How do you do.
BRIGADIER: His number two, Doctor Quinn.
QUINN: Hello.
DOCTOR: Hello, Doctor Quinn.
BRIGADIER: Major Baker, station security officer. Doctor Lawrence, perhaps you'd be good enough to put my colleagues in the picture.
LAWRENCE: This establishment consists basically of a device for research into the nature of the atom. Cyclotron, otherwise known as a proton accelerator. It, er
(The Doctor wanders round the room.)
LAWRENCE: It bombards atoms with subatomic particles.
DOCTOR: Why?
LAWRENCE: We are on the verge of discovering a way to provide cheap, safe, atomic energy for virtually every kind of use.
QUINN: We're developing a new kind of nuclear reactor, one which converts nuclear energy directly to electrical power.
DOCTOR: Yes, well, that's all very well, but what is going wrong?
BRIGADIER: Two things. First, an abnormally high rate of personnel trouble. Nervous breakdowns. Absenteeism. Accidents. But the really serious problem, is the power losses.
LAWRENCE: There have been a certain number of unexplained leakages in the power supplied by the nuclear generator. I am confident we shall find an explanation.
BRIGADIER: You haven't found one yet, Doctor Lawrence. That's why I'm here.
QUINN: Well, it's a highly complex piece of machinery. Naturally there are problems.
DOCTOR: Naturally.
BRIGADIER: Now there are three possible approaches to this problem. Security.
BAKER: Everything has been double-checked.
BRIGADIER: Then you will triple-check it, Major Baker, under my supervision, clear?
BAKER: Sir.
BRIGADIER: Personnel. This will be dealt with by Miss Shaw.
LIZ: Oh, yes?
BRIGADIER: Yes. Finally, the purely scientific angle. Now, the Doctor here. What is it, Doctor? 
DOCTOR: It's the most extraordinary thing. I can't seem to find my sonic screwdriver anywhere.
LAWRENCE: You're not proposing to dismantle a piece of equipment worth fifteen million pounds with a screwdriver?
DOCTOR: Well, it's not worth fifteen million pins if it doesn't work, is it?
BRIGADIER: Doctor, I suggest you start by just looking round.
QUINN: Yes, let me take you both over the installation.
DOCTOR: Splendid. Come on, Liz. Doctor Quinn, which way do we go?
QUINN: To the left.
DOCTOR: To the left.
(Liz, the Doctor and Quinn leave.)
LAWRENCE: Brigadier, I shall expect to hear from you as soon as you've anything to report. You'll see that our work is disrupted as little as possible.
BRIGADIER: Of course, sir. I'll use this room as my HQ if I may.
LAWRENCE: Very well. And, er, I should be grateful if you could hurry things up, Brigadier. I want this place working normally again.
BRIGADIER: We all do, sir.
(Lawrence leaves. Baker looks outside to make sure that he has gone.)
BAKER: I must say, sir, that I fail to see the necessity for the involvement of UNIT.
BRIGADIER: How long have these disturbances been going on?
BAKER: Three months.
BRIGADIER: There's your answer.
BAKER: Sir?
BRIGADIER: Something's been happening here which is outside the normal security pattern, and that is precisely the business of UNIT.
BAKER: Sir. I think I have the solution.
BRIGADIER: Have you?
BAKER: Someone has been carrying out a planned, deliberate programme of sabotage from the inside.

[Cyclotron control room]

(The lady scientist Quinn bumped into is speaking into a microphone as Liz and the Doctor enter with Quinn.)
DAWSON: Electron voltage readings
QUINN: Here we are. Can you manage? Now this is the very
DAWSON: Initiate circuit check.
QUINN: Heart of the cyclotron. Literally so. In fact, we're actually inside the machine itself.
(On the other side of the glass screens, scientists work near a large circular device in the wall which is pulsing pink.)
DOCTOR: You have your own nuclear reactor then?
QUINN: Oh, yes. Oh, yes. The cyclotron uses power in enormous quantities. Would you care to step down?

[Cyclotron room]

DOCTOR: What happens if one of these power losses occurs at a particularly crucial time?
QUINN: So far, we've always managed to stabilise.
LIZ: If you didn't?
QUINN: Well, theoretically
DOCTOR: Your nuclear reactor could turn into a massive atomic bomb.
LIZ: You ought to shut down the place at once.
QUINN: That would be a decision for the Director.
DOCTOR: A decision he might be reluctant to make?
QUINN: Doctor Lawrence has the research programme very much at heart.
(Liz is suddenly slightly dizzy.)
LIZ: Oh. I think I'd better make a start on the personnel files. I wonder if someone could show me where to go.
QUINN: Oh yes, of course. Mister Roberts, take this young lady across to Doctor Meredith in the medical wing, will you?
DOCTOR: Are you all right, Liz?
LIZ: Yes, yes, I'm fine.
ROBERTS: (a nice trimmed beard) Yes, of course. Come this way, please.
DOCTOR: I'll join you later, Liz.
LIZ: Okay.
(Roberts and Liz leave.)
QUINN: You don't mind if I carry on?
DOCTOR: No, no, please do.
(Quinn works at a control desk.)
DOCTOR: Quite an achievement, building this centre in these caves.
QUINN: Yes, there are miles of them still in their natural state. Breathtaking. Ever been potholing?
DOCTOR: No, not for a very long time.
QUINN: No, well I'm very keen on it. At least I was, until
DOCTOR: Until what?
QUINN: A couple of our junior technicians went exploring on their day off. There was an accident, one of them was killed. The other is still in the sickbay.
DOCTOR: You have your own doctor?
QUINN: No. Doctor Meredith comes in from the local hospital.
DOCTOR: This technician, was he badly hurt?
QUINN: Well, now, I'm not sure. They seem to be hushing it up.
DOCTOR: I wonder why.
QUINN: I beg your pardon?
DOCTOR: I said, I wonder why. Doctor Quinn, these power losses, do they take any particular pattern?
QUINN: As far as we can see, completely random.
DOCTOR: I see. Well, I wonder whether I could possibly check. A fresh eye, you know.
QUINN: Oh yes, of course. Here's the log.
(The desk phone rings as Quinn hands over a file.)
QUINN: Excuse me a moment. Quinn here. No, no, no, two three six today. Now get that right. Two three six. Yes, indeed.
DOCTOR: Doctor Quinn?
QUINN: Excuse me. Yes?
DOCTOR: This log seems to be incomplete.
QUINN: Look, I'll ring you back. That log should be kept every day. (into microphone) Miss Dawson?
DAWSON: Yes, Doctor Quinn?
QUINN: Come down here a moment will you?
(Dawson enters.)
QUINN: What an extraordinary thing.
DOCTOR: Hmm.
QUINN: Miss Dawson, there's a query here. Perhaps you can help. Do you know who usually keeps this log?
DAWSON: Oh, it used to be Spencer.
QUINN: Ah, well, that explains it. Spencer's the chap who got hurt in the caves.
DOCTOR: No, Doctor Quinn. I don't think it does explain it. Look.
QUINN: At what?
DOCTOR: There at the bottom of the page, by the string, the binding? You'll see a tiny shred of paper. Some of those pages have been torn out.

[Records office]

(Liz is going through filing cabinets.)
MEREDITH: I might be able to help you, if you could only tell me what you were looking for.
LIZ: I don't know myself yet, Doctor Meredith.
MEREDITH: We've had a lot of trouble of course. Mild neuroses, imaginative ailments, one nervous breakdown.
LIZ: Yes, so I see.
MEREDITH: But of course these things are quite unavoidable.
LIZ: This isn't the only atomic research establishment in the country, you know.
MEREDITH: The others haven't quite the same problem. Working continuously underground you hardly know day from night down here.
(The Doctor enters.)
DOCTOR: Ah, Liz, any luck with those records?
MEREDITH: I take it you're yet another member of the UNIT team?
DOCTOR: Yes. Depressing, isn't it.
LIZ: This is Doctor Meredith.
DOCTOR: Oh, splendid. Just the chap I wanted to see. Now look, this patient of yours, Spencer, the one who was injured in the caves. May I see him?
MEREDITH: I'm sorry, that's quite out of the question.
DOCTOR: Oh, really? Why's that?
MEREDITH: Because I won't allow it, that's why. I'm about to have him moved into hospital. Besides, you have no authority.
DOCTOR: Doctor Meredith, as an associate of UNIT, I think you will find that I have the authority to do precisely as I please. May I now see your patient?
MEREDITH: Oh, it seems I have no choice. All right, but I warn you, it is at your own risk.
DOCTOR: Thank you.

[Sickbay]

(Spencer is doing cave paintings on the wall. Deer, rhino, and a reptilian biped with three eyes...)
DOCTOR: How long has he been behaving like this?
MEREDITH: Since he came out of his coma, with occasional spells of trying to throttle me.
DOCTOR: Astonishing. It's quite astonishing.
MEREDITH: It's the only thing that keeps him quiet.
DOCTOR: Was he much of an artist before the accident?
MEREDITH: Not that I know of.
DOCTOR: Excuse me. It's absolutely amazing.
LIZ: Careful, Doctor.
DOCTOR: Yes, all right, Liz.
(The Doctor kneels behind Spencer and taps him on the back.)
DOCTOR: What's this one, old chap?
(Spencer panics.)
DOCTOR: It's all right, old chap. It's all right.
(Spencer starts to strangle the Doctor.)
DOCTOR: Take it easy.
(Liz and Meredith come to help.)
DOCTOR: Keep away, Doctor. Leave this to me. It's all right, old chap. Now calm down. Settle down now.
(The Doctor pushes Spencer's hands away from his throat.)
DOCTOR: Calm down. That's it. Steady down now. That's it. Calm down. Nobody's going to hurt you.
MEREDITH: Are you all right? I did warn you.
DOCTOR: Yes, I'm all right. He's just frightened, that's all.
LIZ: So was I. What's made him like this?
DOCTOR: Some kind of fear. It's absolutely incredible. It's thrown his mind back millions of years!

[Cyclotron control room]

(A UNIT soldier is standing guard by the door.)
QUINN: Twenty four thirty five.
ROBERTS: Check.
QUINN: Twenty eight over two.
ROBERTS: Check.
QUINN: Forty seven. Hello, there's something wrong there, isn't there? Ah, no wonder. The T one four's not working. You test it today?
DAWSON: Doctor Quinn, the secondary readings.
QUINN: Roberts, would you mind testing the T one four?
ROBERTS: Yes, sir.
(Roberts goes down into the main room. Dawson goes to Quinn and whispers to him.)
DAWSON: I'm frightened. What's going to happen?
QUINN: You mustn't panic. Just behave normally.
DAWSON: This UNIT investigation, they're bound to discover something.
QUINN: I know, it's a risk.
ROBERTS [OC]: Twenty four, power normal.
QUINN: Good.
DAWSON: John, you've got to tell them to stop. At least while these people are here.
QUINN: Do you think I haven't? Either they don't listen, or they don't understand.
DAWSON: They've got to stop!
QUINN: Shush.
ROBERTS [OC]: T one four, S K.
QUINN: Thank you, Roberts.
DAWSON: Tell the Brigadier or Baker, they'll help. Before someone else gets killed.
QUINN: They wouldn't believe me, and anyway there's far too much at stake. Now take your hand off.
DAWSON: It's not worth the risk.
QUINN: The knowledge I shall gain is worth any risk.

[Conference room]

(The Brigadier hands back a file to Baker. A soldier is unpacking other files.)
BRIGADIER: It's very comprehensive, Major Baker.
BAKER: Not quite, sir. There's you and your team.
BRIGADIER: No doubt you'll see to that.
BAKER: Yes, sir. I checked on your security clearance as soon as you arrived. Miss Shaw's clearance has just come through.
BRIGADIER: You're very thorough.
BAKER: This man you call the Doctor, sir, there is nothing on file at central intelligence records about him.
BRIGADIER: No, there wouldn't be.
BAKER: Then may I ask, sir
BRIGADIER: No, Major Baker, you may not. The Doctor is my personal responsibility. (The Doctor enters.)
DOCTOR: Oh, yes, very homely.
BRIGADIER: Right, thank you, Major Baker. We'll have another go at those files later.
BAKER: Sir. I shall be in my office, sir.
(Baker leaves with the file in his briefcase.)
DOCTOR: Where exactly is his office?
BRIGADIER: The other end of the corridor.
DOCTOR: He's very conscientious, isn't he?
BRIGADIER: Well, he slipped up badly once some years ago, he's been trying to make up for it ever since. You'd better look out, Doctor. He wants to run a security check on you.
DOCTOR: I wish him joy of it.
BRIGADIER: I don't suppose you've found anything?
DOCTOR: On the contrary. I've found enough to make me very, very worried.

[Cyclotron control room]

QUINN: Stand by, stand by.
LAWRENCE: Everything normal, Doctor Quinn?
QUINN: Everything is perfectly normal, thank you, Director. We've just completed final checks.
LAWRENCE: Oh good.
QUINN: I'd like to include some of these supplementary tests.
LAWRENCE: And have our schedule fall even further behind? With UNIT looking over our shoulder? No, I don't think so.
(Lawrence leaves.)
QUINN: Stand by. Prepare to initiate program two three six.

[Cyclotron room]

DAWSON: Two three six. Check.
QUINN [OC]: Proton acceleration, phase three.
DAWSON: Phase three. Check.
QUINN [OC]: Roberts, electron voltage reading please.
(But Roberts is staring at nothing.)
DAWSON: Roberts! Electron voltage readings!
ROBERTS: Sorry, sir. Electron voltage reading, two thousand million, power rising.

[Cyclotron control room]

QUINN: Thank you.

[Conference room]

BRIGADIER: Cave drawings on the walls? My dear Doctor, if that's what you call evidence.
DOCTOR: Of course it's evidence.
BRIGADIER: Look, this poor devil sees his friend killed in an accident, he wanders around those caves for hours before they get him out, well quite naturally he has some kind of breakdown.
DOCTOR: Which turns him into a brilliant Paleolithic cave artist? What about the logs, then? Those torn out pages?
BRIGADIER: Now there you may have something. Could be sabotage, I suppose.
DOCTOR: Ah!
BRIGADIER: Or someone trying to cover up simple incompetence.
DOCTOR: Lethbridge-Stewart, what on earth is the point of my trying to discover things for you if you keep turning them down all the time.
BRIGADIER: Then I suggest you discover something I can't dismiss.
DOCTOR: You're not exactly a little Sherlock Holmes yourself, are you?
(The air conditioning goes quiet and the lights dim.)
DOCTOR: What the devil's that?
BRIGADIER: It's another power failure. Come on, Doctor Watson.

[Cyclotron room]

ROBERTS: Power very erratic, sir.

[Cyclotron control room]

(Scientists are rushing in and through to the cyclotron proper.)
ROBERTS [OC]: It keeps dropping off, and then suddenly there's a boost.
(Lawrence enters.)
LAWRENCE: Get that reaction back under control, Doctor Quinn. Shall I take over? 
QUINN: That won't be necessary, thank you. Stand by. We are going to close down in carefully measured stages.

[Cyclotron room]

QUINN [OC]: There is no need for panic. Just follow normal routine.
DAWSON: Proton acceleration very irregular.
(The pink throb is rainbow coloured now.)

[Cyclotron control room]

QUINN: Close down sector one.
(The Doctor and the Brigadier enter.)
QUINN: Electron voltage readings, please.

[Cyclotron room]

DAWSON: Six thousand million, still rising.

[Cyclotron control room]

ROBERTS [OC]: Sector one closed down, sir.
BRIGADIER: What's going on?
QUINN: Close down sector two.
DOCTOR: They're trying to close down the cyclotron without the nuclear reactions getting out of control.
ROBERTS [OC] Sector two closed down, sir.
BRIGADIER: I hope they can manage it. Anything we can do?
DOCTOR: Yes. Keep out of the way, I should think.
QUINN: Close down sector three.

[Cyclotron room]

DAWSON: Power still fluctuating.
QUINN [OC]: Roberts, close down sector three.
ROBERTS: No, it's no good. I can't!
DAWSON: The power is back on full. Proton acceleration seven thousand million, still rising. Roberts! Roberts! Roberts!
(Dawson goes to Roberts' control panel and he drags her away with his hands around her neck. She screams. The Doctor and Brigadier grab Roberts.)
QUINN [OC]: Shut down sector three.

[Cyclotron control room]

QUINN: Someone take over. Shut down sector three.

[Cyclotron room]

(The Doctor does the deed.)
DOCTOR: Sector three shut down.
QUINN [OC]: Thank you, Doctor. Close down sector four.

[Records office]

DOCTOR: Now what about those records, Liz.
LIZ: Well, there's a terrifically high rate of minor neuroses. Two hundred percent above the normal, even for a place like this.
DOCTOR: Any pattern?
LIZ: Everyone who was affected worked at one time or another in the cyclotron room. Even I felt odd while I was there.
DOCTOR: Really? In what way?
LIZ: A feeling of oppression, almost terror.
DOCTOR: You know, it's obviously something that only affects some humans. Otherwise they'd all crack up.
LIZ: So you too think it's something to do with the cyclotron room?
DOCTOR: No, well, not really, but it is the deepest part of the centre. And it's the nearest to those caves.
LIZ: So?
DOCTOR: Everything leads back to those caves, Liz. Davis was killed there. Spencer was frightened into becoming a cave man.
LIZ: That reminds me. There's a report here on Davis.
DOCTOR: Oh, yes?
LIZ: The police forwarded a copy.
DOCTOR: Let's have a look.
LIZ: Even a map showing where they found him.
DOCTOR: Oh good. (reads) Immediate cause of death, fracture of the cranium. Further observations, unusual abrasions on the body, strangely resembling scratches or claw marks. Presumably caused during fall. Claw marks?

[Caves]

(Suitably attired, the Doctor climbs down the ladder and almost immediately hears a roar in the distance. He looks around and finds a caver's hammer in the gravel, then further along a coil of rope. The roar is closer. He enters the area of the original attack and is about to leave again when there is another roar. The Doctor turns to see what looks like a dinosaur standing over him.)

Episode Two

[Caves]

(As the Doctor drops to the ground, shielding his face from the approaching talons, there are three distinct notes repeated over and over again. The dinosaur leaves. The Doctor goes into the next cave and looks at the yard-long footprint it has left.)

[Conference room]

(The Brigadier points to a map of the caves with his swagger stick.)
BRIGADIER: You're sure this is where he's making for?
LIZ: Pretty sure. He wanted to see the exact place where the accident happened.
BRIGADIER: I must say, Miss Shaw, if only you'd come to me earlier.
LIZ: I'm sorry but he asked me not to tell you.
BRIGADIER: I could have sent down a search party immediately.
LIZ: That's just what he didn't want.
BRIGADIER: He deserves all he gets. No sense at all.
(Baker enters with helmets and rope.)
BAKER: I've collected all the equipment I can lay my hands on, and I've alerted the local rescue team. They'll mount a follow-up search as soon as they can.
LIZ: This is very good of you, Major Baker.
BRIGADIER: I'm only sorry that a member of my staff should be causing so much trouble. We're supposed to be helping you.
BAKER: The main thing is to get your Doctor out of those caves as soon as possible. How many men have you, sir?
BRIGADIER: Five or six, and Captain Hawkins. More on the way from HQ.
BAKER: Well, I suggest we start a preliminary search just as soon as we can.
BRIGADIER: Right. We'll be ready to go in five minutes.
BAKER: Right sir.
DOCTOR: Well, this all looks very exciting. May I come too?

[Cyclotron room]

LAWRENCE: Surely you must have found some explanation.
QUINN: Both generator and cyclotron are functioning perfectly. Excuse me. Miss Dawson, electron voltage readings please.
DAWSON [OC]: Two thousand million, power steady, all systems at normal.
LAWRENCE: Everything's in perfect order, except for the fact that these power losses still keep on recurring.
QUINN: We are trying everything possible.
LAWRENCE: Yes, I know. I'm sorry.

[Cyclotron control room]

QUINN: Thank you, Miss Dawson.
LAWRENCE: This project started off so well. Still, we're not the only ones with problems.
QUINN: Oh?
LAWRENCE: UNIT. That ridiculous Doctor of theirs got himself lost in the caves.
QUINN: Are they searching for him?
LAWRENCE: They were, but the fellow turned up again.
QUINN: That's very fortunate.
LAWRENCE: Let me know if you find anything wrong, won't you.
QUINN: Yes of course.
(Lawrence leaves.)
DAWSON: If they had started searching those caves
QUINN: Well, they're not going to, are they, so we needn't worry.

[Conference room]

(The Doctor is in his normal clothes again.)
DOCTOR: Anybody would think you were disappointed that I didn't get lost.
LIZ: Come on, Doctor. You get everyone worried, then turn up safe and sound.
BAKER: You shouldn't have gone, sir.
DOCTOR: Well, it produced results, didn't it?
BRIGADIER: Subterranean Loch Ness monster? Very helpful.
DOCTOR: Oh, so you don't believe me?
BRIGADIER: Oh, I believe you saw something. The question is what.
LIZ: You weren't very specific.
DOCTOR: Well, I hardly had time to draw its picture, did I? All I can tell you is that it was something very, very large, and something very, very alive.
LIZ: Could it have been prehistoric?
DOCTOR: Well, it was certainly some kind of dinosaur. Certainly nothing that I've ever seen before, though.
BAKER: In museums, you mean?
DOCTOR: No, I do not mean in museums. Well, on second thoughts, perhaps, perhaps I do, yes.
BAKER: Look, sir. Suppose there is sabotage going on, and a large group hiding in the caves have faked up some kind of monster.
LIZ: To scare people away?
BAKER: And to account for the unexplained deaths. The noise the Doctor heard could have been machinery.
BRIGADIER: What do you think, Doctor?
DOCTOR: Well, it's a possibility. I suppose.
BRIGADIER: Well, whatever it is, we must check up on it.
BAKER: I'll be glad to go with you sir.
BRIGADIER: We'll all go, except Miss Shaw.
LIZ: Oh, just a minute. I'm not going to miss all the fun
BRIGADIER: No, Miss Shaw.
LIZ: Have you never heard of female emancipation?
DOCTOR: Liz, this time I think he's right.
BAKER: Your men will be armed, sir?
BRIGADIER: Small arms, grenades, nothing very substantial.
BAKER: We'll be a bit short on firepower.
DOCTOR: That's typical of the military mind, isn't it? Present them with a new problem, and they start shooting at it.
BRIGADIER: Yes, well, I'll inform the Director of my decision.
DOCTOR: It's not the only way, you know, just blasting away at things!
(The Brigadier leaves.)
BAKER: Oh don't worry, Doctor, we'll make sure your prehistoric friend gets a sporting chance. We won't shoot until we see the whites of its eyes, huh?

[Caves]

(The Doctor leads the party.)
DOCTOR: I found the footprint over here somewhere.
(No dent in the gravel.)
BRIGADIER: Well, Doctor?
DOCTOR: Well it was here. Well, it's dried up, isn't it. Anyone can see that.
BRIGADIER: I'm afraid I can't see anything at all.
(A rumbling noise.)
BAKER: Listen! Shall I take a look, sir?
BRIGADIER: Yes all right. Captain Hawkins, take a couple of men and go with Major Baker.
HAWKINS: Very good sir. You two come with me. Major Baker! Come on, you two. Wait for us, sir! 
(Everyone say Hi to Paul Darrow making his first Who appearance.)

[Cave tunnels]

(Baker sees a figure ahead.)
BAKER: Hey, you there! Halt or I fire!
(He shoots and it staggers out of sight. There is a roar, Baker turns and fires at the dinosaur before its claw crashes down on him. His scream is heard down the tunnel. Then the three notes are played.)
DOCTOR: Come on!
(Hawkins and the Doctor arrive at Baker's position first, followed by the Brigadier and the soldiers.)
BRIGADIER: What happened, Hawkins?
HAWKINS: No idea, sir. We found him like this when we got here.
DOCTOR: It's all right, old chap. Take it easy. Take it easy.
BAKER: I saw someone down there. I fired over his head. I think I hit him. Ricochet.
BRIGADIER: Did he attack you?
BAKER: No, something else. Bullets, bullets wouldn't stop, stop it!
DOCTOR: It's all right, old chap. Take it easy. Hold him there.
BRIGADIER: Get the first aid kit, and a shot of morphine. We'd better get him back to the centre.
HAWKINS: Very good, sir.
BRIGADIER: Oh, Captain Hawkins?
HAWKINS: Sir?
BRIGADIER: Before you do that, take a look up there and be careful.
HAWKINS: Sir.
(Hawkins goes further up the tunnel, pistol drawn. The Doctor is holding Baker's rifle, its barrel bent ninety degrees.)
BRIGADIER: What do you make of it, Doctor?
DOCTOR: Well, obviously Baker shot at something he thought was a man. Then something else attacked Baker.
BRIGADIER: The prehistoric creature that attacked you?
DOCTOR: Oh, it seems very likely, doesn't it.
HAWKINS: Sir? Something over here sir.

[Cavern]

HAWKINS: Ricochet marks on the rocks, sir. And look over here, sir. Traces of blood, spots leading this way.
BRIGADIER: We'd better follow them. Doctor?
DOCTOR: No. I'll get back to the hospital with these blood samples. In any case I can give a hand to carry Baker.
BRIGADIER: Right. Morton, give the Doctor a hand. The rest, follow me.
DOCTOR: Brigadier! You'll be careful, won't you? After all, you don't really know what you're following, you know.
(On Wenley Moor, as the sun sets, we see a three-fingered claw, then a scale-covered biped climbs out of the ground. We get a sample of its vision which is binocular plus an upper red tinted triangular section. It staggers away, gasping, and hides in some scrubby bushes.)

[Research Centre Laboratory]

(The Doctor is examining the blood sample with a microscope.)
LIZ: Well, Doctor?
DOCTOR: Well, see for yourself.
LIZ: Well, I know this may seem a little far-fetched, but there are resemblances to
DOCTOR: Certain of the larger reptiles?
LIZ: Yes.
DOCTOR: Precisely.
(The Brigadier enters.)
BRIGADIER: Bad news, Doctor. We lost it.
DOCTOR: Oh, no.
BRIGADIER: Well there's a lot of moorland out there. Anyway, it was getting dark.
DOCTOR: Yes, I suppose so.
LIZ: What are you going to do now?
BRIGADIER: I've sent to HQ for some more men. We'll mount a full-scale search in the morning. Doctor, have you got any idea what we're looking for?
DOCTOR: No, not yet. So far our tests have proved inconclusive.
BRIGADIER: There'll be the devil to pay if Baker shot some innocent potholer. Oh, how is he, by the way?
LIZ: Well there was some bruising, and one arm was clawed, and there's a possibility of mild concussion.
DOCTOR: Poor chap. Mind you, he was behaving very irresponsibly, blazing away like that.
BRIGADIER: He was attacked, Doctor, just as you were.
DOCTOR: Yes, but not by the thing that he shot at. Seems to me, Brigadier, that you're missing the most important point.
BRIGADIER: Which is?
DOCTOR: That when Baker was attacked, and when I was attacked, the thing was called off before it could do any real harm.
LIZ: Davis was killed though.
DOCTOR: Yes, I know, but in my opinion there are two kinds of creature down in that cave. A large and ferocious one, and a smaller, much more intelligent kind that controls the first, and may not be hostile.
BRIGADIER: It's a bit hard to accept one monster, let alone two. Still, whatever it is, we'll know in the morning.
DOCTOR: Yes and by that time it might be a little too late.
(Under cover of darkness, the injured reptile enters a farmyard, goes to a barn and falls into the bales of hay.)

[Cyclotron control room]

LAWRENCE: Simply to disappear at a time like this!
DAWSON: Doctor Quinn has been working very long hours under a considerable strain.
LAWRENCE: So have we all.
(The Doctor enters.)
DOCTOR: Oh, I'm so sorry. I was looking for Doctor Quinn.
LAWRENCE: You're not the only one.
DAWSON: He completed as many of the tests as he could, and then he simply had to go and rest.
DOCTOR: Is he in his quarters?
DAWSON: Well, no.
LAWRENCE: Gone off to that cottage of his, has he? If he spent more time doing his job and less writing that book of his. When he gets back, tell him I'd like to see him, would you? If he can spare a moment.
(Lawrence leaves.)
DOCTOR: Don't worry, my dear. We're all under a bit of a strain at the moment.
DAWSON: Doctor Quinn works harder than anyone at this centre.
DOCTOR: Yes, yes, yes. Yes, I'm sure he does. It's just that I'd rather like another word with him myself. It's about those power losses.

[Silurian control room]

(Quinn is underground, using a map to find his way. Something scaly is watching him. He arrives at an area where one part of the wall is smooth and stands still. A red light shines down on him. Rigid and staring upwards, he turns around as a door opens in the smooth wall and walks through. A little way along the green walled corridor another red light hits him. He raises his arms and walks through into a room with alien control panels and leans back against a sort of chair, his hands on its projecting arms. The red light goes off.)
SILURIAN [OC]: Why have you come?
QUINN: I have come to warn you. There are men searching the caves. Soldiers with weapons.
SILURIAN [OC]: Your warning is too late. They have already attacked us.
QUINN: What happened?
SILURIAN [OC]: One of us was wounded. He was forced onto the surface.
QUINN: Were any humans hurt?
SILURIAN [OC]: That does not concern us.
QUINN: You must stop taking power from the cyclotron.
SILURIAN [OC]: We still need the power. We are not yet ready to make our own.
QUINN: It's causing endless trouble. That's what brought the soldiers here.
SILURIAN [OC]: One us of was wounded. We need your help to recover him.
QUINN: How do you expect me to do that? The soldiers will be hunting for him. They will see me. I tell you it's impossible. I won't do it.
SILURIAN [OC]: You refuse to help us, yet you expect our scientists to give you their secrets?
QUINN: All you've given me so far are scraps of knowledge, hints. I must know.
SILURIAN [OC]: You will be given the information when the wounded one is returned to us.
QUINN: Very well. What shall I do? How can I find him?
SILURIAN [OC]: We will give you a summoning device. He will hear it and come to you.
(A triangular device with a oblong switch on the top is by the chair. Quinn picks it up then the red light comes on. His arms go up and he leaves.)

[Squire's farm - barn]

(Daybreak, and the farmer comes out of the stables and goes across to the hay barn. He sticks his pitchfork in and uncovers a scaly claw then runs to the barn door.)
SQUIRE: Doris! Doris!
DORIS [OC]: What do you want?
SQUIRE: Get on to the police. Tell them there's something in my barn!
DORIS [OC]: What sort of something?
SQUIRE: Some sort of freak! I saw it move in the hay!
(But he isn't seeing it sneak up behind him.)
SQUIRE: Well, get on with it, woman!
(Squire hears its heavy breathing and turns, pitchfork at the ready. But he is felled by one stroke of its claw, and screams. Doris comes in and screams, too.)

[Conference room]

(It has been turned into a proper field HQ with several desks and telephones.)
HAWKINS: Everything's organised, sir. The chopper's already up and there are two platoons in support.
BRIGADIER: Good. Ask Major Peters to keep the men on stand by. I'll be with him as soon as I can.
HAWKINS: Very good, sir. (into phone) Major Peters, please.
(Lawrence enters.)
BRIGADIER: Good morning, Director. I was about to come and see you.
LAWRENCE: I realise you must be busy, particularly since you seem to be engaged in a full-scale military operation with my research centre as it's HQ.
BRIGADIER: Yes, I apologise for the inconvenience, Director.
LAWRENCE: When you and your associates descended upon us, not I might add at any request of mine, I understood that your purpose was to put an end to the setbacks that have been plaguing us here.
BRIGADIER: That is true, sir.
LAWRENCE: And what have you achieved?
BRIGADIER: To begin with, Miss Shaw has discovered an abnormally high rate of stress symptoms amongst your staff.
LAWRENCE: There's bound to be a few weak links. What about these power losses?
BRIGADIER: The Doctor has spent most of the night examining the equipment here.
LAWRENCE: Ah yes, your mysterious Doctor with his sonic screwdriver. Is he qualified to make such an investigation?
(The Doctor enters.)
BRIGADIER: The Doctor's qualified to do almost everything.
DOCTOR: Well, that's it then. There's nothing wrong with it.
BRIGADIER: Nothing wrong with what?
DOCTOR: With any of it. Cyclotron, remote control mechanisms, all of them functioning perfectly.
LAWRENCE: You can't possibly be sure.
DOCTOR: My dear man, it's a perfectly simple piece of machinery.
LAWRENCE: Oh? Then what is the explanation of these power losses? Magic?
DOCTOR: The power from your reactor, like the mental state of your staff, has been affected by some outside influence.
LAWRENCE: Indeed. And what do you propose to do about it?
DOCTOR: It's more a question of what you propose to do about it. Until this influence has been discovered and dealt with, this establishment should be closed down completely.
LAWRENCE: Out of the question. It would mean a tremendous setback to our research programme.
DOCTOR: And to your career?
LAWRENCE: I'm extremely dissatisfied, Brigadier, with your conduct of this investigation, and with the behaviour of your associate. I intend to write to the Permanent Under-Secretary, and demand your recall.
BRIGADIER: That is your privilege, Director, but whilst we are here perhaps you'd let us carry on with our investigations.
(Lawrence leaves.)
DOCTOR: Pompous idiot! Never could stand that man. Well, Brigadier, all set to start playing soldiers, are we?
(The Brigadier answers his phone.)
BRIGADIER: Lethbridge-Stewart. Yes. Yes. I see. Thank you very much. I'll be there as soon as I can. Police. I asked them to let me know of any unusual occurrences.
DOCTOR: And?
BRIGADIER: Local farmer named Squire found dead in his barn. There were claw marks on his body.

[Squire's barn]

DOCTOR: Poor chap.
LIZ: Are they the same marks as you found on Davis in the caves?
DOCTOR: Oh no, these were made by something quite different. Smaller perhaps, but very powerful.
BRIGADIER: I thought you said the thing wasn't hostile.
DOCTOR: Yes, but I imagine that Squire attacked him with this. (pitchfork) May have been cornered. What about the man's wife?
BRIGADIER: She's at the local hospital suffering from shock.
DOCTOR: Yes, well, I'd like a word with her. Perhaps you'd like to stay and do some forensic tests, Liz.
LIZ: Yes, of course.
DOCTOR: Those claw marks. They weren't the cause of death, you know.
BRIGADIER: Then what was?
DOCTOR: Heart failure. You might say he died of fear.

[Hospital ward]

DOCTOR: Now please, I want you tell me. What happened to your husband? Can you remember what happened to him?
(Doris stares into the air, gasping with fear and whimpering.)
DOCTOR: She was found in the barn, paralysed with fear. She may have seen something. Have you got a pen?
BRIGADIER: Yes.
DOCTOR: And the chart please. Chart!
(The Doctor starts scribbling over Doris' medical chart.)
DOCTOR: Now, I want you to take a look at this. Have you ever seen anything like this before.
(The Doctor shows Doris his drawing of a reptile with three eyes.)
DOCTOR: Yes? What?
DORIS: Killed him!
DOCTOR: Yes?
DORIS: Killed him!
DOCTOR: What happened then? Where did he go?
DORIS: It's there.
DOCTOR: Where?
DORIS: In the barn.
DOCTOR: In the barn?
DORIS: In the barn.
DOCTOR: Still there!
BRIGADIER: Miss Shaw!

[Squire's barn]

(Liz is kneeling in the hay collecting blood samples. The Silurian is up in the hay loft watching her. As she has her back to it, it comes down the steps and approaches. Liz turns at the sound of heavy breathing, and screams as a claw lashes out at her face, knocking her sideways.)

Episode Three

[Squire's barn]

(The Silurian goes to the barn door and sees a policeman getting out of a car in the yard. It bolts the door.)

[Quinn's cottage]

(Quinn is looking for a map when Dawson enters.)
QUINN: Oh, it's you.
DAWSON: The front door was open.
QUINN: What do you want?
DAWSON: I wanted to know if you were all right. Doctor Lawrence has been asking where you are.
QUINN: There are more important things than Doctor Lawrence. Ah, here we are.
DAWSON: What are you doing?
(Quinn unfolds the cave map.)
QUINN: Yes. Look.
(He puts the Silurian device on the table.)
QUINN: They gave it to me.
DAWSON: What on earth is it?
QUINN: The product of another civilisation. It's a communications device.
DAWSON: You've seen them?
QUINN: No, but they trust me and they want me to help them.
DAWSON: How?
QUINN: That fool Baker wounded one of them. I have to get it back to the caves. It will respond to this.
DAWSON: That must have been what the soldiers were searching for.
QUINN: What?
DAWSON: The Doctor and the Brigadier rushed down to that farm near the research centre.
QUINN: Why? Do you know why?
DAWSON: Something happened there. Someone was hurt.
QUINN: Squire's Farm? There's a cave opening near there. Perhaps it? Yes, it must have come up from the cave opening and made its way straight to the farm. Yes, that's it. That must be it.
DAWSON: What do I tell Doctor Lawrence?
QUINN: Tell him what you like.

[Squire's barn]

(Outside the barn, a soldier is trying to pry open the door. The Brigadier looks through a crack in the wood to see Liz lying in the hay. Finally the door is open and they rush. The Doctor goes straight to Liz.) 
BRIGADIER: Captain Hawkins!
HAWKINS: Sir!
BRIGADIER: All right, Sergeant, search the place.
(Hawkins and a soldier go up into the hay loft as other soldiers spread out downstairs and an ambulance man goes to the Doctor and Liz. There is a noise, but it is just a chicken. They go down again.)
BRIGADIER: All right, panic over. There's nothing there.
HAWKINS: It must be somewhere, sir. The door was bolted on the inside.
DOCTOR: All right, officer. We can manage.
(A policeman leaves.)
BRIGADIER: What happened?
DOCTOR: Well, give her a moment. She's just coming round.
(Liz pushes herself up to show the scrapes on her cheek.)
LIZ: I saw it.
HAWKINS: Sir, over here. Look.
(There is a hole in the barn wall by a stack of hay bales.)
BRIGADIER: I want the whole area searched. The fields, outbuildings, everywhere.
HAWKINS: Right, sir.
DOCTOR: Now, Liz, this thing. What did it look like?
LIZ: It was like a reptile, but it walked upright like a man.
(In the pouring rain outside, Quinn drives in and parks his car next to Bessie.)
DOCTOR: Here you are, Liz. Come and sit on this. There we are. How are you feeling now?
LIZ: Better, thanks. Headache's a bit bad.
DOCTOR: Well, I'm not surprised.
(Quinn enters.)
QUINN: Ah. What's happening?
DOCTOR: Doctor Quinn. How did you get here?
QUINN: I was on my way back to the research centre. I saw all the police and soldiers outside.
DOCTOR: Ah, so you're feeling better then?
QUINN: Better?
DOCTOR: I understood you didn't feel too well.
QUINN: Oh yes, yes. No, I went back to my cottage. I'm all right now.
DOCTOR: Whereabouts is your cottage?
QUINN: By the lake, just north of the centre. What's happened to you? Are you all right?
LIZ: Something attacked me.
QUINN: What sort of thing?
LIZ: Like a
DOCTOR: Well, we don't know. Yet.
BRIGADIER: Everything's organised. The chopper's already up.
QUINN: Well, I'd better get out of the way. Clearly you're all very busy.
BRIGADIER: Oh, one moment, Doctor Quinn.
QUINN: Yes?
BRIGADIER: Just a thought. Perhaps you could help us? You know this district. If you wanted to hide, where would you go?

[Wenley Moor]

(A helicopter swoops low. Police dogs sniff their way through the heather. Captain Hawkins fires off a flare and watches a line of searchers through his binoculars. He uses his radio.)
HAWKINS: Watchdog to Windmill one two three. How do you read me? Over.
WINDMILL [OC]: Loud and clear, Watchdog. Have searched area one. No sign of anything. Commencing search of area two. Over.
(The helicopter flies off.)
HAWKINS: Watchdog to Windmill one two three. Message understood. Over and out.

[Squire's barn]

(Liz, the Doctor, Quinn and the Brigadier are studying a map.)
QUINN: I'm sorry I can't be more help. There's a lot of wild country around here.
BRIGADIER: Well, thanks anyway. We'll cover the whole area.
QUINN: Well, I really must be getting back to the centre.
DOCTOR: Doctor Quinn. I wonder whether you'd mind giving Miss Shaw a lift.
QUINN: I'm sorry, I can't.
DOCTOR: But I thought you were going straight back there.
QUINN: I'm going to the garage in the village first. There's something wrong with my car. It might take some time.
BRIGADIER: Not to worry. I'll send her back in a police car.
QUINN: Oh, I'll get along then. Excuse me.
(Quinn leaves.)
BRIGADIER: Yes, well, I'll get that laid on.
(The Brigadier leaves.)
LIZ: Doctor, look at the map.
DOCTOR: Hmm?
LIZ: Doctor Quinn's cottage is here, and the village is here.
DOCTOR: Well?
LIZ: This farm is miles out of his way.

[Wenley Moor]

(Quinn drives along a track then stops and gets out of his car. He walks a little way then switches on the Silurian device. It makes the same three tone noise we heard call off the dinosaur. A police dog hears it and starts barking. The UNIT helicopter flies low along the track. Quinn notices it and turns the device off, putting it in his pocket. He waves at the helicopter as it flies past then goes back to his car.)
WINDMILL [OC]: Windmill one two three to Watchdog.
(Quinn drives on. Elsewhere, Bessie is approaching Hawkins' Land Rover.)
HAWKINS: Watchdog to Windmill one two three. Message understood. Over and out.
BRIGADIER: Any luck, Captain?
HAWKINS: Oh, I'm not quite sure, sir. The helicopter reports seeing a man standing by his car in the north west sector of area two, sir.
BRIGADIER: Well?
HAWKINS: Well, apparently he just waved and drove off.
BRIGADIER: Probably another potholer.
HAWKINS: Yes sir. But there is something else.
BRIGADIER: Yes?
HAWKINS: Well, a moment ago I thought I heard a funny kind of a noise, sir.
BRIGADIER: Well, what kind of noise?
HAWKINS: Rather like that sound we heard in the cave, sir.
DOCTOR: Hmm. What direction did it come from?
HAWKINS: Well, that also came from the north west sector of area two, sir.
(The Doctor and Brigadier drive away. On another track, Quinn has the device signalling before he parks up by a small clump of young fir trees. The signal is very fast now. The Silurian approaches and the signal is so fast it is almost one sound. Quinn turns and sees it. On another road, the Doctor stops Bessie.)
BRIGADIER: That noise. It stopped.
DOCTOR: Yes. I'm sure it came from over there. Let's go and have a look.
(Everyone is closing in on the place where Quinn parked.)
BRIGADIER: Doctor, stop!
(The Doctor stops Bessie and the Brigadier gets out to look at three-toed tracks in the mud.)
BRIGADIER: Look at these. Are these the same as the footprints as you saw in the cave?
DOCTOR: No, this is smaller. These are the footprints of a biped.
BRIGADIER: Then the thing can't be far from here.
DOCTOR: Here, look at these.
BRIGADIER: Car tracks.
DOCTOR: Anyone bringing a car here would be miles out of his way.
BRIGADIER: What's that?
DOCTOR: Oh nothing. Just a thought.
BRIGADIER: I'll get the men.
(The Brigadier extends the aerial on his hi-tech walkie-talkie.)
BRIGADIER: UNIT commander to all sections. All parties to converge on south east sector area three. I repeat, all parties to converge on south east sector area three.

[Sickbay]

LIZ: Major Baker! It's all right. How are you?
(The male nurse who had been adjusting Baker's sling leaves.)
BAKER: How are you?
LIZ: Oh, all right, thanks.
BAKER: Did the Brigadier get my message?
LIZ: Yes, he asked me to come and see you.
BAKER: And?
LIZ: You're to stay here till you're better. How's the arm?
BAKER: Oh, it's perfectly all right. Look, I have got to get out of here.
LIZ: Just as soon as Doctor Meredith says so. There's still a chance you may have concussion.
BAKER: Oh, rubbish.
LIZ: How much do you remember of what happened to you?
BAKER: Everything! I saw this man. He must have been a saboteur. I took a shot at him, and then. And then I. Everything went black. Oh look, isn't the Brigadier taking any action?
LIZ: I'm sure he is. Just leave it to him. Look, I must go.
BAKER: Miss Shaw. Please, I have got to see the Brigadier.
LIZ: No! I'm sorry.
(Liz leaves. Baker takes off his sling and starts to unbutton his pajama top.)

[Quinn's cottage]

(A car pulls up outside and a door slams. Quinn goes to the door then walks away just before the doorbell rings. He slowly goes to open it.)
QUINN: Yes?
DOCTOR: I thought you were going straight back to the research centre.
QUINN: Yes, yes, I am.
DOCTOR: Only I saw your car was still parked outside. I thought perhaps you might have been taken ill again.
QUINN: No, no, I'm perfectly all right, thank you. I just had to come back for something, that's all
(Quinn tries to shut the door but the Doctor stops it with his foot and enters.)
DOCTOR: What a charming place. Mmm, charming. Lovely old grandfather clock. Is this the living room? Oh yes, very nice. Very nice. Had the place long, have you?
QUINN: No, I bought it a few months after I got the job here. Look Doctor, I'm sorry but I really have to be
DOCTOR: Centrally heated too, eh?
QUINN: It gets very cold up here.
DOCTOR: Yes. Still, you do keep it very warm though, don't you?
QUINN: Yes, well, the thermostat's jammed, you see. I'm having it fixed.
DOCTOR: Perhaps you'd like me to look at it for you, I like tinkering with these gadgets.
QUINN: That's very kind of you but I've already sent for the people who installed it.
DOCTOR: Good, good. Only it is rather like the reptile house in the zoo, isn't it?
QUINN: What do you mean? Eh? What do you mean?
DOCTOR: Nothing. I was just referring to the temperature of the room.
QUINN: Doctor, I'm sorry but I really must ask you to leave. There's something very urgent I have to do before I go back to the centre.
DOCTOR: Oh? Yes, yes, of course. I'm so sorry to have taken up so much of your time.
QUINN: Not at all. I'm only sorry that I seem to have been rather
DOCTOR: My word, it's just as hot out here, isn't it? You really must get that thermostat fixed, you know. Anything wrong?
QUINN: Er, no.
DOCTOR: You'd save yourself a lot of trouble if you'd let me help you. They didn't catch it, you know.

[Quinn's office]

(The Doctor and Liz are going through papers.)
LIZ: Look, what exactly are we looking for?
DOCTOR: Anything. I must know more about Doctor Quinn.
(The Doctor goes to a cupboard.)
DOCTOR: Hand me that paper knife, Liz, will you?
LIZ: Yes, here.
DOCTOR: Thank you.
LIZ: What do you think you're doing?
DOCTOR: Breaking open the cabinet, m'dear. He's not going to leave anything important just lying around, is he? There we are. Now then, what have we got here? Pitons, notes. What's this? Let's have a look at these.
(The Doctor takes out a blue and brown ball, and a file.)
LIZ: What's that?
DOCTOR: Some kind of a ball. It's got some markings on it. Have a look.
LIZ: It's a globe. Surely that's the shape of the west coast of America. No. No, the land mass is all bunched together
DOCTOR: What's that? Let me have a look at that. Of course. This is the world as it was before the great continental drift, two hundred million years ago. And these notes, well, they're calculations on the age of the earth, with particular reference to the Silurian era.
DAWSON: What are you doing in here? This is Doctor Quinn's private office! I shall have to inform the Director about this.
DOCTOR: That won't help Doctor Quinn, will it?
DAWSON: What are you talking about?
DOCTOR: I'm talking about the caves, Miss Dawson.
DAWSON: What about them?
DOCTOR: There's something down there, and I think Doctor Quinn knows what it is. Now look, you must tell me what you know, Miss Dawson, before anybody else gets killed. Maybe even Doctor Quinn.
DAWSON: Oh, I warned him.
DOCTOR: Warned him? Warned him about what?
DAWSON: I promised not to tell anyone, but if Doctor Quinn is in danger, I
BRIGADIER: Ah Doctor, we're due for a meeting with
DOCTOR: Yes, Miss Dawson?
DAWSON: I'm sorry, Doctor, I can't help you. If you'll excuse me.
(Dawson leaves.)
BRIGADIER: What was all that about?
DOCTOR: Never mind, Lethbridge-Stewart, it's too late now.

[Quinn's cottage]

(Quinn is bringing in a bucket of firewood when the doorbell rings. Quinn waits in the darkened living room as someone enters the cottage and comes into the room. He turns on the lights.)
DAWSON: Oh!
QUINN: What do you want?
DAWSON: That Doctor, the one with UNIT, I caught him searching your office.
QUINN: He had no right.
DAWSON: You can't go on like this. Don't you realise? People are being killed, and it's your fault. You've got to tell someone.
QUINN: No. Not until I'm ready.
DAWSON: Oh John, please. Please, let me tell this Doctor. He'll believe you. He wants to help you.
QUINN: He's a scientist, too. He only wants to steal the credit for my discoveries.
DAWSON: What discoveries? They haven't told you anything yet.
QUINN: They will now. I can make them.
DAWSON: You can't make them do anything.
QUINN: I've got one of them here. The one they were hunting. I've got it locked up.
DAWSON: But it might kill you. It's already killed that farmer.
QUINN: That creature in there is a scientist. With the knowledge it can give me, I can prove
DAWSON: It won't give you anything!
QUINN: Unless I get it back to the caves it will die. And I won't take it back until it tells me what I want to know.

[Conference room]

DOCTOR: Look, I tell you, gentlemen, that the interference is definitely coming from those caves!
BAKER: (entering) Exactly, Doctor. This centre is being sabotaged.
BRIGADIER: Major Baker, you are supposed to be in the Sickbay.
BAKER: I am perfectly all right, thank you. I propose that we move down there in force, sir.
DOCTOR: That, Major Baker, is precisely what we must not do at this present time.
BAKER: I insist that you take some positive action.
BRIGADIER: I shall decide what action I shall take, and you, Major Baker, will return to the Sickbay and remain there till I send for you.
BAKER: Oh, this is ridiculous!
BRIGADIER: And that will be all, Major Baker. Captain Hawkins, you will accompany Major Baker to the Sickbay and see that he remains there.
HAWKINS: Sir!
(Baker and Hawkins leave.)
LAWRENCE: Do I now take it you have arrested my security officer?
BRIGADIER: Major Baker isn't himself.
DOCTOR: I must say, Brigadier, that I'm delighted that you didn't agree with him.
BRIGADIER: Oh but I do. I intend to send for more men and mount a full scale search of those caves.
DOCTOR: Now look if you'd just give me a little more time
BRIGADIER: I'm sorry, Doctor. My mind is made up.
LAWRENCE: I advise you to do your best to achieve some kind of results in the time available to you.
BRIGADIER: Sir?
LAWRENCE: Masters, the Permanent Under-Secretary, is coming down here to conduct a personal investigation. Unless you can impress him more than you impress me, you may well find yourself transferred to some simpler duties, more within your scope.
BRIGADIER: Doctor Lawrence, as I believe I have told you before
(Lawrence and the Brigadier leave.)
DOCTOR: Stupid bumbling idiots, the pair of them.
LIZ: Now where are you going?
DOCTOR: To see Doctor Quinn. I must persuade him to trust me before it's too late.

[Quinn's cottage]

(Once again the doorbell rings through the dark rooms. The Doctor shines his torch through the window then opens the door.)
DOCTOR: Doctor Quinn? Doctor Quinn?
(The Doctor enters the hallway. A Silurian hand is on a half door behind him as he enters the living room where he sees Quinn in an easy chair.)
DOCTOR: Doctor Quinn? Quinn?
(Quinn's eyes are open but he does not respond when the Doctor waves his hand in front of them, so the Doctor checks for a heartbeat then stands and closes Quinn's eyes. The Doctor takes the Silurian device from Quinn's cold hand and switches it on. The Silurian enters.)

Episode Four

[Quinn's cottage]

DOCTOR: Hello! Are you a Silurian?
(The Doctor holds out his hand and the Silurian gazes at it, withdrawing its claw.)
DOCTOR: Look, do you understand me? (a nod) Well, what do your people want? How can we help you? How many are there of you? Tell us what we can do!
(At the sound of a car outside, the Silurian pushes the Doctor aside and bursts through the back door into the night.)
DOCTOR: No, wait! Wait! Wait! Unless you Silurians tell us what you want, the humans will destroy you!

[Sickbay]

(Baker is lying on the bed, making notes from a map of the caves. He sees a soldier walk past, and hides the map under his pillow and the notebook in his jacket pocket.)
BAKER: Sergeant.
HART: Sir.
BAKER: Are you still standing guard over me?
HART: Sorry, sir. Brigadier's orders.
BAKER: I see. Well, as long as you're here, you may as well give me a hand. Would you help me off with my jacket? My arm's still a bit stiff.
HART: Certainly, sir.
BAKER: Oh steady, now, steady. It's still a bit painful.
HART: Yes, of course, sir.
BAKER: Thank you.
(Hart takes the jacket and turns. Baker chops him across the back of the neck, grabs his jacket back and runs.)

[Conference room]

BRIGADIER: And you just let him walk away?
HART: Yes, sir.
BRIGADIER: Sergeant Hart, you were told to see that Major Baker remained in the Sickbay.
HART: I know, sir, but he jumped me.
BRIGADIER: You should have been prepared for that.
HART: But I thought he was ill, sir. He said he couldn't use his arm.
BRIGADIER: He seems to have used it on you all right.
HART: Yes, sir. Do you want me to set up a search party, sir?
BRIGADIER: No. Dismissed.
HART: Sir!
(Hart leaves.)
LIZ: Surely you're going to look for Major Baker?
BRIGADIER: He'll be in those caves, looking for those saboteurs of his. We'll find him when we move in.
(He is right, of course. Baker is using his notes to find his way through. He steps through a tunnel into a puddle of bubbling liquid, and cannot move his feet. Silurians appear behind him. Baker turns and tries to fire his rifle at them, but they easily hide behind stalagmites. Finally one gets up close. He throws his rifle at it as the third eye glows red and he collapses.)
LIZ: You're still going ahead with your plans to invade the caves? Whatever the Doctor says?
BRIGADIER: I've sent to HQ for reinforcements. They should be here by dawn. Look, where is the Doctor?
LIZ: I'm not quite sure. I believe he mentioned visiting Doctor Quinn.
BRIGADIER: I didn't bring him down here to visit the sick.
(The Doctor enters.)
LIZ: Hello.
DOCTOR: Hello.
LIZ: Was Quinn any help?
DOCTOR: No. No, I'm afraid not.
BRIGADIER: What's Doctor Quinn got to do with it?
DOCTOR: He was, is very interested in potholing, I thought his experience with the caves might have been useful.
BRIGADIER: May I remind you, Doctor, that your business here is to investigate these power failures. Now, do you have any suggestions to make?
DOCTOR: Oh, yes. That this establishment should be closed down completely.
BRIGADIER: Not much chance of Doctor Lawrence agreeing to that.
DOCTOR: And a planned, cautious, scientific investigation of those caves. Not an invasion by a lot of big-booted soldiers.
BRIGADIER: There are times, Doctor, when you sorely try my patience.
(The Brigadier and the other UNIT personnel leave.)
LIZ: What's wrong, Doctor? What happened when you saw Quinn?
DOCTOR: Sit down, Liz. Quinn's dead. He's been killed.
LIZ: Oh, no.
DOCTOR: By a Silurian.
LIZ: A Silurian?
DOCTOR: Probably the same creature that attacked you.
LIZ: You saw it?
DOCTOR: I spoke to it. And it understood me.
LIZ: What was it like?
DOCTOR: Reptilian. Biped. A completely alien species.
LIZ: And it didn't attack you?
DOCTOR: Liz, these creatures aren't just animals. They're an alien life form, as intelligent as we are.
LIZ: Why didn't you tell the Brigadier?
DOCTOR: Because I want to find out more about these creatures. They're not necessarily hostile.
LIZ: Doctor, it attacked me.
DOCTOR: Yes, but only to escape. It didn't kill you. It didn't attack me when I was in Quinn's cottage. Well, don't you see? They only attack for survival. Well, human beings behave in very much the same way.
LIZ: What are we going to do now?
DOCTOR: Well, I'm going back down into those caves, see what I can find out.
LIZ: Then I'm coming with you.
DOCTOR: No, Liz.
LIZ: Either I come with you or I go straight to the Brigadier.
DOCTOR: All right. Have it your own way. But the fate be on your own head. Here, you take a look at this.
LIZ: What is it?
DOCTOR: It's a map of the caves that I found in Quinn's office. And look here. He's marked a special route to somewhere.

[Caves]

DOCTOR: I think this is right. Hang on a minute, I'm not so sure.
LIZ: Well, what about this way, then?
DOCTOR: No, Quinn's marked a completely different route, look.
LIZ: Yes, but look, that's far more direct.
DOCTOR: Yes, all right. Here, wait a minute.
(The Doctor stops before the pool of liquid and picks up a shell casing.)
DOCTOR: Look at that. A cartridge. Just been fired, too.
LIZ: Hey, look.
(Liz picks up a notebook.)
DOCTOR: Well, that's Baker's.
LIZ: We've got to find him.
DOCTOR: Liz, wait a minute.
(The Doctor picks up a rock and drops it into the liquid, which starts bubbling.)
LIZ: Oh, no.
DOCTOR: Yes, well, from now on I think we'd better stick rigidly to Quinn's route.
LIZ: Yes.
DOCTOR: Come on.
(Liz gasps.)
DOCTOR: What's the matter?
LIZ: It's this heat.
DOCTOR: Yes, I know. It's very odd.
(Further on they come to the smooth wall.)
LIZ: Doctor, look!
DOCTOR: Well, well, well.
LIZ: It's a doorway.
DOCTOR: Yes, well, anyone can see that. The question is, how do you open it?
LIZ: Doctor. A Silurian.
(The Doctor and Liz hide as the figure approaches the door. A few familiar beeps and the door opens and it goes through. The door shuts again.)
DOCTOR: I can't understand why it didn't see us.
(Liz touches the door.)
LIZ: Ow!
DOCTOR: What's the matter?
LIZ: Why is it so hot?
DOCTOR: Well, the Silurians are reptilian, you see. They've presumably created an environment inside there that suits them.
LIZ: I wonder how many of them there are.
DOCTOR: Well, I wish I knew. There's only one way of finding out, that's to get in there and see.
LIZ: Well, we can't without one of those things it was carrying.
DOCTOR: Yes, of course.
LIZ: I suppose you just happen to have one in your pocket?
DOCTOR: As a matter of fact I have. Quinn's.
(The Doctor activates the Silurian device and the door opens for them.)

[Silurian cages]

(Just inside the base they hide as a Silurian comes out of a room and goes along the corridor. They sneak past the opening, unnoticed by the Silurian sitting at a control panel. A little further on is a metal cage with one annoyed inhabitant.)
BAKER: How long are you leaving me in here? They'll be coming after me you know.
(His Silurian guard goes back up the corridor to the room. The Doctor and Liz approach from the rear of the cage.)
DOCTOR: (sotto) Baker!
BAKER: How did you get in here? Where are the troops?
DOCTOR: I'm sorry, but we're alone.
BAKER: Well, you've got to get back. Tell the Brigadier.
LIZ: Can't we get you out of here?
BAKER: No, there's not a chance. There's some sort of electronic lock.
DOCTOR: Have they harmed you at all?
BAKER: No, they just keep asking a lot of questions.
DOCTOR: They can talk to you?
BAKER: Yes.
DOCTOR: What do they ask?
BAKER: The population of the earth, what weapons we use, what food we eat. Don't you see? They are trying to gather information for an invasion!
DOCTOR: Look, if they speak to you again, co-operate with them a little. Find out all you can about them.
(Liz hears a mechanical noise.)
LIZ: What's that?
(In the next compartment, a casket opens and a Silurian slowly gets out.)
LIZ: What are they doing?
DOCTOR: They're trying to revive a Silurian from some sort of deep hibernation. Maybe that explains the power losses in the research centre.
BAKER: (sotto) Doctor! Look, this is your chance. Get moving.
LIZ: We can't just leave you here.
BAKER: Go on, get out of here, will you, or we'll all be their prisoners.
DOCTOR: All right, we'll get back for you as soon as we possibly can.
BAKER: Fine.
DOCTOR: Good luck.
(The Doctor and Liz go back down the corridor and stop by the room.)
LIZ: There's three of them in there now. One of them's bound to see us.
(They return to the cage and Baker points at another corridor.)
BAKER: Try.
DOCTOR: Let's try this way.
(They go down another corridor. Liz gasps in horror as they pass a room with a transparent door.)
DOCTOR: That's the creature that attacked me in the caves! They must turn it loose sometimes and use it as some kind of a watchdog.
LIZ: Those creatures died out millions of years ago.
DOCTOR: Apparently not, Liz.

[Cyclotron control room]

(The cyclotron is glowing deep red again.)
TRAVIS: Close down sector three.
TECH 1 [OC]: Sector three closed down.
TRAVIS: Electron voltage reading.
TECH 1 [OC]: Two thousand million. Falling.
TRAVIS: Close down sector four.
TECH 2 [OC]: Sector four closed down.
TRAVIS: Stabilise all sectors. Maintain close down.
TECH 3 [OC]: All sectors stabilised.
(Lawrence rushes in.)
LAWRENCE: What is it, Travis?
TRAVIS: Another power loss, sir. We were making the hourly circuit check when it registered.
LAWRENCE: Have you stabilised the nuclear reaction?
TRAVIS: Yes, sir. We shut down at once.
(Lawrence picks up the phone.)
LAWRENCE: Lawrence here. Get me the generating area.
TRAVIS: I've already checked, sir. Nothing wrong there.
LAWRENCE: I see. All right, forget it. Get me Doctor Quinn at his home.
TRAVIS: I've tried that, sir. There's no reply.
LAWRENCE: Cancel the call. Where's Miss Dawson? Isn't this her shift?
TRAVIS: She didn't report in, sir. And there's no reply from her quarters.
LAWRENCE: Oh, this is absurd!
(The phone rings. Travis gets there first.)
TRAVIS: Excuse me, sir. Travis. Yes, he's here. All right, I'll tell him. The Permanent Under-Secretary, sir.
LAWRENCE: What are you doing, man? Let me speak to him.
TRAVIS: There's no need, sir. I meant he's actually here in the centre. He's on his way down in the lift now.
LAWRENCE: That's all I need.
TRAVIS: What's he come here for, sir?
LAWRENCE: I sent for him!
(Geoffrey Palmer enters.)
MASTERS: Hello, Charles.
LAWRENCE: Oh, Edward.
MASTERS: What's all this about?
LAWRENCE: I didn't expect to see you till much later.
MASTERS: I've got to report to a meeting in London tomorrow. Any chance of some coffee?
LAWRENCE: Coffee?
MASTERS: I have been travelling most of the night.
LAWRENCE: Oh yes, of course, I'm sorry. Let's go to my conference room. It's this way.

[Conference room]

MASTERS: UNIT?
LAWRENCE: As you can see, they're well established.
(Masters heads straight for the coffee machine.)
MASTERS: Lethbridge-Stewart is asking for more troops.
LAWRENCE: Yeah, to go chasing about on some sort of man hunt. Nothing's been done about the power failures.
MASTERS: We've got to get this sorted out, you know. I'm under very heavy pressure from the Minister. The future of this centre is very much in question.
LAWRENCE: Ah, but surely
MASTERS: You've made great promises for this project, Charles. Nuclear power into electricity. Limitless supplies of cheap, safe energy.
LAWRENCE: And we can do it, too.
MASTERS: Millions of pounds have been poured into this place with no results to show for it.
LAWRENCE: But if this research centre is abandoned, all of that money will be wasted.
MASTERS: It would mean the end of your career, Charles. That's why I'm doing my best for you. What does your security man have to say about all this?
LAWRENCE: Major Baker is convinced there are saboteurs in the caves.
MASTERS: And are there?
LAWRENCE: Well, of course not.
MASTERS: How can you be so sure?
LAWRENCE: Well, the whole thing's ridiculous. The Brigadier and Baker talk of saboteurs, and that Doctor believes there are monsters down there.
MASTERS: I beg your pardon?
LAWRENCE: Didn't the Brigadier put that in his report?
MASTERS: He was a little vague about the precise nature of the menace.
LAWRENCE: That's scarcely surprising. Look, Edward, I admit we've had a number of technical setbacks. Mine is not an easy job, you know.
MASTERS: I realise that.
LAWRENCE: Our problems can only be solved by scientists, not by security men.
MASTERS: What do you want me to do.
LAWRENCE: Get all these UNIT people out of my way. Let me get on with my job.
MASTERS: The Brigadier is only trying to help you.
LAWRENCE: Help me? He's exaggerating this whole business out of all proportion merely to magnify his own importance.
MASTERS: I hardly think that's justified.
LAWRENCE: Well you don't know him as well as I do. I
MASTERS: I'm not arguing with you, man. I'm simply trying to find a solution to the problem. The Brigadier and his team have come down here with
LAWRENCE: His team? What, that girl and that crazy Doctor?
MASTERS: The Doctor is supposed to be brilliant, in his own way. He may be a little eccentric.
LAWRENCE: The man's a raving lunatic! He's insolent, he's impertinent, he shows no respect for my authority.
(The Doctor and Liz enter.)
DOCTOR: Ah, Doctor Lawrence. Just the man I wanted to see. Now tell me, have you just had a power failure?
LAWRENCE: Yes. How did you know?
DOCTOR: I see, thank you.
LAWRENCE: Now just a minute. This is the Permanent Under-Secretary.
DOCTOR: Yes, well, I've got no time to chat to under-secretaries, permanent or otherwise. I must find the Brigadier.
MASTERS: May I ask who you are?
DOCTOR: You may ask.
(The Brigadier enters.)
DOCTOR: Ah, there you are.
BRIGADIER: I've only just heard that you were here. I've been trying to get in touch with you. Look, sir, what's happening about my reinforcements?
MASTERS: That's one of the reasons why I'm here. I'm afraid you're not going to get any reinforcements.
BRIGADIER: May I ask why not?
MASTERS: I can't go to the Minister of Defence and request regular Army support for you on the basis of a wild tale about monsters in caves.
BRIGADIER: Sir, we have overwhelming evidence that there is something in those caves.
MASTERS: Do you mean saboteurs?
BRIGADIER: I don't know, but the caves are vast. To cover them properly I must have more men!
MASTERS: I'm sorry, that's out of the question.
BRIGADIER: Then I'll have to go in with the troops I have.
DOCTOR: Brigadier, you are not to take your men into those caves. I've been down there and I know what's happening.
MASTERS: Well, if you do, perhaps you'd be good enough to tell us.
BRIGADIER: Yes, Doctor. I think you'd better.

[Silurian cages]

(Two Silurians are interrogating Baker. The first is old and experienced, the second young and impulsive.)
SILURIAN: You must answer our questions.
BAKER: I am not refusing, am I?
SILURIAN: Is your species the only intelligent lifeform?
BAKER: Only intelligent lifeform? Oh, I see what you mean. Yes, of course we are.
SILURIAN JR: You were carrying a simple projectile weapon. Do all your species carry these weapons?
BAKER: Of course not. Only soldiers.
SILURIAN JR: What other weapons do your soldiers carry?
BAKER: I refuse to answer that sort of question.
SILURIAN: You must answer.
BAKER: You can do what you like, I will not tell you anything. I will not tell you anything!
SILURIAN: The creature is becoming aggressive again.
SILURIAN JR: I will force it to answer.
(The Silurian pulls back Junior's claw.)
SILURIAN: I do not wish it to be damaged. This creature is less intelligent. Quinn should not have been killed.
SILURIAN JR: But he tried to keep one of us prisoner.
SILURIAN: This strange species has developed some kind of civilisation. We need to study it.
SILURIAN JR: The species is dangerous and hostile. We should kill them all.

[Conference room]

LAWRENCE: And are you suggesting that these Silurians are responsible for the power losses?
LIZ: Some of them are still in hibernation. The others use the power to bring them back to life.
BRIGADIER: What weapons do they have?
DOCTOR: Huh. Spoken like a true soldier.
BRIGADIER: It is my job, Doctor. How many are there?
DOCTOR: Well, we don't know. Maybe there are thousands.
LAWRENCE: Then you must deal with them promptly, Brigadier. If they exist.
DOCTOR: Look, Mister Under-Secretary, surely this is a government matter. It cannot be decided at this level.
MASTERS: Doctor, whether I believe you or not, I can't go back to the Minister with a story like this. There's no proof except your word.
BRIGADIER: I'll find all the proof you need. Look, Doctor, I'm not going down there to start a war, but I must know what's going on.
DOCTOR: If you go down there with a party of armed men there's bound to be fighting.
LAWRENCE: What is your alternative, Doctor?
DOCTOR: Well, leave them alone. Let me try and make contact with them.
MASTERS: Are you really convinced these Silurians aren't savage?
DOCTOR: Well, so far they've only attacked in self-defence. At least let's give them the benefit of the doubt.
(Dawson enters slowly, in her raincoat.)
LAWRENCE: Miss Dawson, where on earth have you been? What's the matter?
DAWSON: Doctor Quinn, he's dead.
LAWRENCE: Dead?
DAWSON: He didn't answer his phone. I went there and found him. The Silurians killed him.
BRIGADIER: What do you know about these creatures?
DAWSON: Doctor Quinn found out about them when he was potholing. He said they had great scientific knowledge. He co-operated with them and they killed him.
BRIGADIER: Now, Doctor, do you still maintain these creatures aren't hostile? I'll continue as planned.
MASTERS: I think you're right.
BRIGADIER: We'll move in first thing in the morning. Oh, Miss Dawson? I'd like a full statement from you, everything you know about this business. Will you come with me, please?
DOCTOR: Miss Dawson, did these Silurians tell Doctor Quinn anything about their intentions?
DAWSON: Intentions? Well, that's obvious, isn't it? We must destroy them, before they destroy us.
(The Brigadier and Dawson leave.)
MASTERS: Charles, we'd better have a word.
(Masters and Lawrence go to the other end of the room.)
LIZ: Now what are you going to do?
DOCTOR: There's only one thing I can do. I've got to get down into those caves and warn the Silurians.
LIZ: What?
DOCTOR: If the Brigadier won't listen to reason, Liz, maybe the Silurians will.
LIZ: Please be careful.

[Silurian control room]

DOCTOR: Ahem. I'm sorry to burst in on you like this.
SILURIAN JR: How did you enter our base?
SILURIAN: Why have you come here?
DOCTOR: I came here to warn you that humans are about to enter your caves.
SILURIAN JR: Shall I destroy him?
SILURIAN: No. Take him to the cages.
DOCTOR: No. You don't understand. No, I've come here to I've come here to warn you.

[Silurian cages]

(The Doctor is dragged down the corridor to where Baker is still held captive. The metal door of the cage next to Baker is opened by the power of the third eye and the Doctor is pushed inside. The door shuts again and the Silurians leave.)
BAKER: What happened? I thought you were going to get help.
DOCTOR: Don't worry, help's on the way. I only wish it weren't.
SILURIAN: I repeat. Why have you come here?
DOCTOR: I came here because I want to help you.
BAKER: Just a minute, what do you think you're doing?
SILURIAN JR: Quiet!
SILURIAN: How can you help us?
DOCTOR: Look, people are coming. Many people are coming here. I want you to meet them in peace.
SILURIAN: Who are these people?
DOCTOR: Well, they're soldiers, but they won't attack you unless you attack them first.
SILURIAN: Why do you want to help us?
DOCTOR: Because I want there to be peace between you and the humans. This is their planet now.
SILURIAN: This planet is ours. It always has been.

[Caves]

BRIGADIER: Map. Well, there should be a way through here.
HAWKINS: Well, either this map's wrong, sir, or we're lost.
BRIGADIER: We'd better go back.
(The party turns around and takes a few steps, then -)
HAWKINS: We've just come through this way. This wall. It wasn't there!

[Silurian cages]

BAKER: You had no right to tell them about the Brigadier's plans.
DOCTOR: I was simply trying to prevent a massacre.
BAKER: What guarantee have you got that these creatures aren't going to set an ambush?
DOCTOR: I had to take that risk. At least there's a chance they won't start killing each other.
(The young Silurian comes up to the cage.)
DOCTOR: Have you seen the humans yet? Have you spoken to them?
SILURIAN JR: I have destroyed them. And now I shall destroy you. (The third eye glows and the Doctor shakes.)

[Episode Five]

[Silurian cages]

SILURIAN: Stop. Do not kill it. It may be useful. Why were you killing it?
(The Silurian pulls Junior away from the cage and Baker catches the Doctor as he falls.)
SILURIAN JR: We have no need for it, or those soldiers sent to attack us. I have dealt with them.
BAKER: Doctor!
SILURIAN: I gave you no orders to do this.
SILURIAN JR: But they were carrying weapons like this one. They can no longer harm us.
SILURIAN: But now they will send others. You forget there are now millions of these men.
SILURIAN JR: Then we shall destroy them all.

[Caves]

(Soldiers are trying to break through the new wall blocking their retreat, while Robins uses the field telephone.)
ROBINS: UNIT leader to base. UNIT leader to base. It's no good, sir.
BRIGADIER: Try once more.
ROBINS: UNIT leader to base. It's dead, sir.
HAWKINS: All right. This is solid rock as well, sir. We'd need explosives to shift it.
BRIGADIER: Yes.
HAWKINS: How can it just appear like that? We were able to walk through there a moment ago, and. Well, what are we going to do, sir?
BRIGADIER: Afraid there's not much we can do. We're trapped.
HAWKINS: I suppose we'll just have to sit and wait until somebody gets us out.
BRIGADIER: We can't afford to wait too long.
HAWKINS: At least we've got food and water.
BRIGADIER: Yes but we have a limited supply of air, and we're using it up all the time.
HAWKINS: How long do you reckon we've got, sir?
BRIGADIER: Two or three hours at the most.

[Conference room]

LIZ: So you see, we haven't been exactly idle down here. Whatever the impression Doctor Lawrence may have given to you.
LAWRENCE: Really, Miss Shaw.
MASTERS: It's a remarkable accumulation of evidence.
LAWRENCE: It's a lot of nonsense. The power losses are a technical problem. All I need is more reliable staff, and more facilities. Not a lot of cloak and dagger people cluttering up the place.
(The phone rings.)
MASTERS: Masters. Yes. Right. Thank you. It was the UNIT people at the cave mouth. They've completely lost contact with the Brigadier.

[Silurian cages]

DOCTOR: Please, you must listen to me. I want to talk to you.
BAKER: What do you think you're doing? Haven't you done enough damage?
DOCTOR: You're making a terrible mistake. I can stop you from being destroyed.
SILURIAN: We have studied your weapons. They are primitive.
DOCTOR: Look, you've got no idea of the fighting power of the humans.
BAKER: Be quiet!
DOCTOR: They've got bombs now that can wipe out whole continents.
BAKER: Shut up!
(Baker grabs at the Doctor, so the Silurian uses his third eye on him. Baker collapses.)
DOCTOR: Please, please, let me out of here. Let me out of here. Can't you see I can do you no possible harm?
(The Silurian unlocks the cage with his third eye.)
SILURIAN: Come with me.

[Caves]

(The air is getting thin.)
HAWKINS: Shouldn't we try and break out again, sir? I know it seems to be hopeless, but at least we'd be doing something.
BRIGADIER: The more we move, the quicker we use up the air. We'll wait. It's our only chance.
HAWKINS: Sir, look.
BRIGADIER: You all right Robins? Robins?
(Robins is shaking and wringing his hands.)
ROBINS: Sir?

[Conference room]

(Masters answers the phone again.)
MASTERS: Masters.
(Dawson enters.)
DAWSON: Excuse me, Doctor
LAWRENCE: One minute, please.
MASTERS: I see. Well, continue the search. Let me know if there's any further news. Search party can't find any trace of the Brigadier.
DAWSON: Search party? Good heavens, if they can't find them they'll be dead by now.
MASTERS: Why do you say that?
DAWSON: I found Doctor Quinn's body. I've seen what these Silurians do.
LAWRENCE: They obviously got lost.
DAWSON: Well then, that's all the more reason to get more men and equipment. You could mount an all-out attack. You could send troops into every one of those caves.
MASTERS: The caves are vast. We'd need hundreds of men.
DAWSON: But there may be hundreds of Silurians down there.
LAWRENCE: Now you don't really believe that.
DAWSON: Yes! You've seen them.
LIZ: Yes, so has the Doctor.
DAWSON: Right. Three people have seen them. They do exist, and we've got to attack them first.
LIZ: Just because they're an alien species, that doesn't mean we have to kill them.
DAWSON: But
LIZ: The Doctor thinks that we should
MASTERS: What, Miss Shaw?
LIZ: Never mind.
MASTERS: Where is the Doctor? Where did he go?
LAWRENCE: Well, Miss Shaw? Where is he?

[Silurian laboratory]

(A Silurian scientist is examining Baker's rifle.)
SILURIAN JR: As a scientist, what have you discovered about this weapon?
SCIENTIST: It projects a small piece of metal at high speed.
SILURIAN JR: Crude. It is a fitting weapon for apes.
SCIENTIST: The device has a certain ingenuity. Remember, one of us was wounded by such a weapon.
SILURIAN JR: The apes have become dangerous. They must be destroyed.
SCIENTIST: Our leader seems to have different views.
SILURIAN JR: I know. He has taken one of these creatures into our control room. He is talking to it.
SCIENTIST: Perhaps it may give him useful information.
SILURIAN JR: What information can we gain from apes? His concern for them may be dangerous!

[Conference room]

MASTERS: Then let me ask you again. Where is the Doctor?
LIZ: He went down into the caves.
LAWRENCE: What?
LIZ: Ahead of the Brigadier. He wanted to make contact with the Silurians.
DAWSON: Make contact?
MASTERS: What was he going to say to them?
LIZ: He thought if he could warn the Silurians first.
DAWSON: He warned them? Why, the Brigadier has probably walked straight into a trap.
LIZ: He wanted to prevent bloodshed.
DAWSON: But
LIZ: He has gone down into those caves to try and help. He is risking his own life.
MASTERS: So now you expect us to send troops down there?
LIZ: No, no, no, that's the last thing he'd want.
DAWSON: Oh, never mind what your Doctor wants, he's done enough damage. Mister Masters, can't you see, you've got to get more troops and destroy these monsters.
MASTERS: The search is still going on. I shall wait until I get another report.
DAWSON: Aren't you going to do anything?
MASTERS: Not for the moment.
DAWSON: But if you don't do something now
MASTERS: I've made my decision, Miss Dawson.

[Silurian control room]

DOCTOR: But you must see this is a highly-developed and overcrowded planet which now belongs to man.
SILURIAN: This is our planet. We were here before man. We ruled this world millions of years ago.
DOCTOR: Then why did you stay down here?
SILURIAN: A small planet was approaching the world. We calculated that it would draw off our atmosphere, destroying all life. We built this place, and suspended our lives till the atmosphere should return.
DOCTOR: A small planet? Yes, of course. But don't you see, that small planet was drawn into the Earth's orbit and became the moon? Your catastrophe never happened.

[Silurian cages],

BAKER: Hey you! Where's the Doctor, what's going on? Well, where is he? What's he telling you? Where are you, Doctor? Telling them everything they want to know? You're nothing but a traitor.

[Silurian control room]

BAKER [OC]: You hear me, Doctor? A traitor!
DOCTOR: But I still don't understand why you stayed down here.
SILURIAN: The hibernation mechanism was faulty. It did not function until a new energy source appeared.
DOCTOR: The power station at the research centre?
SILURIAN: Yes. We are now able to drain off its energy. But soon we shall revive our civilisation, and reclaim the Earth for ourselves.
DOCTOR: No, you mustn't, otherwise there'll be the most terrible war.
SILURIAN: You
DOCTOR: But if you trust me, I think I can persuade the humans that you are prepared to live with them on this planet in peace.
SILURIAN: There is not room for both civilisations.
DOCTOR: Oh yes, I think there is. You see, your people are used to living in extreme heat, whereas these areas on Earth are of little interest to man. I believe with your advanced technology that you could build cities in parts of the world that man has hitherto completely ignored.
SILURIAN: Would your people agree to this?
DOCTOR: Well, they're not my people, but I think I could convince them, on the condition that you release those trapped men first.
SILURIAN: Those apes have only shown hostility to us.
DOCTOR: And you to them. Someone has to make a move, otherwise this whole thing will end up in complete catastrophe.

[Caves]

(The troops are sitting, saving their air and energy, except for Robins who is doing cave drawings.)
HAWKINS: What's that? You all right, Robins? Robins?
(Hawkins touches Robins, who attacks him.)
ROBINS: Leave me alone!
(Robins returns to his scratching.)
HAWKINS: What's the matter with him?
BRIGADIER: Same thing happened to one of the scientists at the research centre. Safer to leave him alone.
(In the control room, the Silurian works a panel with his third eye. A wall of rock disappears in the cave.)
HAWKINS: Sir, look, it's opening again.

[Silurian Control room]

SILURIAN: The humans have been released.
DOCTOR: Thank you for your trust in me. I only hope it will not be in vain.
SILURIAN JR: Why have you released the apes?
SILURIAN: I have decided that it is possible for the two species to live together on this planet.
SILURIAN JR: This planet is ours!
SILURIAN: This other species has developed its own civilisation. We must accept them as equals.
SILURIAN JR: I disagree! We must destroy them!

[Silurian laboratory]

(The scientist is reviewing mammalian species, comparing chimpanzees with Baker.)
SILURIAN JR: He talks of sharing our planet with apes! I shall wipe them out!
SCIENTIST: You have no right to disobey him. He is our leader.
SILURIAN JR: Perhaps he is no longer fit to lead us. Soon I shall be the leader. Help me, or must I destroy you too?
SCIENTIST: Very well. I will help you. When the apes used to raid our crops we used this.
(The Scientist picks up a vial of liquid.)
SCIENTIST: Millions were wiped out. Now, we could conduct an experiment on this ape.
SILURIAN JR: Yes.

[Silurian cages]

(Junior opens Baker's cage.)
SILURIAN JR: Leave the cage.
BAKER: Why? Where are you taking me?
SILURIAN JR: Leave the cage!
(Baker pushes Junior aside and runs down the corridor but his way is blocked. He runs round the area looking for escape.)
SILURIAN JR: Do not kill it. Do not kill it! We need this creature alive!
BAKER: Oh, no.
(Baker is grabbed by a Silurian but fights it off. Finally he is surrounded.)
BAKER: Oh. All right, all right. You win.
(Baker ducks underneath the Silurian's outstretched arms and runs down the corridor to the dinosaur's area. This time a Silurian knocks Baker out.)
SCIENTIST: Take him to my laboratory. We shall use this creature to destroy all its kind.

[Conference room]

(Everyone is staring at the telephone.)
DAWSON: How much longer are we going to wait?
MASTERS: Search party hasn't reported back yet.
LAWRENCE: Perhaps we should send another search party to look for them?
MASTERS: Charles, please.
LAWRENCE: Well, it's so ridiculous, all these people chasing about the caves. How is it supposed to solve my problems?
LIZ: The Brigadier and the Doctor are risking their lives trying to solve your problems.
LAWRENCE: That's a matter of opinion.
DAWSON: Well, it's obvious what we should be doing, we should be attacking in force.
LIZ: Oh, don't be so
MASTERS: We'll get nowhere by bickering amongst ourselves.
LAWRENCE: You don't understand
(The Brigadier enters.)
LIZ: Brigadier! Thank goodness! Come and sit down.
BRIGADIER: It's all right, Miss Shaw.
LIZ: What's happened? Come on, sit down, please.
MASTERS: What's happened?
BRIGADIER: We were trapped in those caves.
DAWSON: Were the Silurians waiting for you?
BRIGADIER: Not exactly. A rock wall appeared in front of us, and then it vanished again.
LAWRENCE: Vanished? More fairy stories, Brigadier?
BRIGADIER: I lost a lot of men in those caves, Doctor Lawrence.
MASTERS: Have you brought the Doctor back?
BRIGADIER: Isn't he here?
MASTERS: He appears to have gone down the caves ahead of you.
BRIGADIER: Whatever for?
LAWRENCE: I shouldn't worry about him, Brigadier. He's probably chatting quite happily to his monster friends.

[Silurian Control room]

SILURIAN: Do I have your assurance that the humans will agree to our sharing the planet?
DOCTOR: You have my assurance that I shall tell them of your desire for peace, yes.
SILURIAN: Very well. I shall explain to the others, so that you may return in safety.
DOCTOR: Thank you.
SILURIAN: You will wait here.
(The Silurian uses his third eye then leaves. The Doctor abruptly discovers that there is a forcefield across the doorway. The Silurians leave Baker in the caves, then wake him using the third eye. They watch him leave.)

[Silurian cages]

SILURIAN: You had no right to do this without my authority.
SILURIAN JR: This is the method we used against them before.
SILURIAN: They were animals then. They are civilised now.
SILURIAN JR: That makes them all the more dangerous to us.
SILURIAN: I do not believe so.
SILURIAN JR: You are no longer fit to lead us.
SILURIAN: I shall destroy you if you defy me again. Now go.

[Silurian Control room]

(The Doctor is viewing Silurian history on a viewscreen. The Silurian removes the forcefield and enters.)
DOCTOR: You once had a great civilisation. I didn't realise how advanced.
SILURIAN: The other prisoner has been released.
DOCTOR: Baker? Why, that's splendid.
SILURIAN: Doctor, listen to me. He has been infected with a deadly disease which may destroy millions of his species.
DOCTOR: But this is diabolical.
SILURIAN: It is not my doing. There are those of us unwilling to share this planet.
DOCTOR: Is there any cure for this disease?
SILURIAN: No. But I have brought the bacteria. Perhaps your scientists can find a cure.
DOCTOR: Yes. Yes, of course, but you must release me at once.
SILURIAN: Come with me.

[Conference room]

BRIGADIER: The men have had a chance to rest now. We'll be setting off in a few minutes. Don't worry, Miss Shaw, we'll find the Doctor.
(Baker enters.)
LIZ: Major Baker! How did you get out? Have you seen the Doctor?
BAKER: Oh yes, I saw him all right, with his Silurian friends!
BRIGADIER: Major Baker, just exactly what are you implying?
BAKER: Huh! They didn't keep him caged up like an animal for very long. He warned them that you were coming, so they could set up an ambush!
LIZ: No, that's not
BAKER: He's gone over to their side!
BRIGADIER: I don't believe that.
MASTERS: Now, wait a minute! They had you caged up? How did you escape?
BAKER: Well, I got away when they weren't looking. Look, it doesn't matter about me. We must blow up every entrance to those caves before the Silurians overrun us!
DOCTOR: That is precisely what we must not do.
BAKER: You!
DOCTOR: Now everyone move well away from Major Baker. Now keep right back from him. Right back.
BAKER: What are you talking about?
DOCTOR: Major Baker, you are ill. You are very, very ill.
BAKER: Oh, you don't get out of it like that. I'm placing you under arrest.
BRIGADIER: Wait
(Baker goes to grab the Doctor, who jumps up onto a table.) 
DOCTOR: Keep back from him! Look at your wrist. Look at it!
(There are pustules on Baker's wrist and forearm. He collapses.)

[Silurian Control room]

SILURIAN JR: Why did you give him the bacteria? Do you want this species to destroy us?
SILURIAN: They will not destroy us, and we need not destroy them. Both species can live together.
SILURIAN JR: That is impossible!
SILURIAN: I am the leader! I have decided!
SILURIAN JR: Not any more!
(Junior uses his third eye on the elder, who flails at his attacker briefly then collapses.)
SILURIAN JR: He was no longer fit to lead us.

[Conference room]

DOCTOR: This whole place should be closed down and put in strict quarantine immediately.
LAWRENCE: It would bring the centre to a standstill.
DOCTOR: Yes, and about time too. Well I've got to get down to the research centre and try to find an antidote.
LAWRENCE: I refuse to permit this. Look, Edward, can't you stop him? This whole story is absurd.
DOCTOR: You just don't understand, do you, Doctor Lawrence?
MASTERS: I'm afraid I don't either. You say these creatures have infected us with a plague, but do you still want us to negotiate with them?
DOCTOR: That is precisely what I want. But if this bacteria isn't contained there won't be anybody left to negotiate.
(Liz enters.)
LIZ: Baker's gone. Doctor Meredith's just taken him to the hospital.
DOCTOR: That's the worst thing that could have happened. Why didn't you stop him?
LIZ: I tried. He wouldn't listen.
DOCTOR: Brigadier, we've got to go down to the hospital straight away before Baker spreads that infection.
BRIGADIER: But surely hospital's the right place for Baker?
DOCTOR: Meredith does not know what he's dealing with. Nobody does! Now please, do as I say.
BRIGADIER: All right. You'll have to excuse me, sir. (Liz, the Doctor and the Brigadier leave.)
LAWRENCE: What do you want me to do?
MASTERS: This could be a national disaster. I must get back to London.
LAWRENCE: What about the research centre?
MASTERS: I'm sorry, Charles, but I intend to recommend that this centre be closed immediately.
LAWRENCE: But all my work? The delay will be crippling.
MASTERS: My report will of course exonerate you completely. I'm sure you've done everything in your power. Well, I must be going.
(Masters sways as he stands up.)
LAWRENCE: Are you feeling all right?
MASTERS: I didn't get any sleep last night. I'll send you a copy of my report.
(Masters leaves.)
LAWRENCE: Thank you, Edward.

[Wenley hospital]

(Bessie hurtles up the driveway as a patient staggers out of the little building and falls to the ground. The Brigadier and the Doctor run over.)
BRIGADIER: Is he dead?
DOCTOR: Yes, the first one.

[Episode Six]

[Wenley hospital]

(A doctor and nurse come out of the building.)
MAN: (Doctor) What's going on here?
BRIGADIER: Keep back.
MAN: What do you mean, keep back? This man is ill.
DOCTOR: This man is dead. He was killed by an alien disease.
MAN: Alien?
(The doctor kneels to examine his former patient, and the Brigadier draws his revolver.)
BRIGADIER: Inside.
MAN: Come on.
(The doctor and nurse return to the building, taking a second nurse with them.)
DOCTOR: Right, you'd better get this place quarantined. I'm going back to the laboratory.
BRIGADIER: Right. I'll stay here.
(The Doctor drives off.)
BRIGADIER: UNIT leader to base. UNIT leader to base.

[Research Station laboratory]

(The Doctor is labeling sample slides ready for testing. Liz enters.)
DOCTOR: Have you finished with those prophylactic injections yet?
LIZ: Yes, nearly. Do you think pumping broad-spectrum antibiotics into everyone is going to do any good?
DOCTOR: It's all we can do at the moment.
LIZ: Will you roll up your sleeve please, Doctor?
DOCTOR: Well, now wait a minute, Liz
LIZ: Now you have been exposed to the infection just as much as everyone else.
DOCTOR: Liz
LIZ: I know all about your different biochemistry, but we don't know if it makes you immune. Now roll up your sleeve. Come on.
DOCTOR: Yes, all right, have it your own way.
(While Liz gives the injection, the Doctor looks up then wipes a bead of moisture from his forehead.)
LIZ: Did it hurt?
DOCTOR: Did what hurt? Oh yes, it was agony.
LIZ: Have you managed to identify the bacterium?
DOCTOR: No, not yet, I'm still waiting for that scanning microscope.
(The Brigadier enters.)
DOCTOR: It's supposed to be on its way.
BRIGADIER: It'll be here, Doctor.
DOCTOR: Well, I'm glad to hear it. Now then, how about that hospital?
BRIGADIER: I've got the entire place cordoned off.
DOCTOR: Good, and your own men?
BRIGADIER: They've all been treated. We've sent in a medical team to help Doctor Meredith in the hospital.
DOCTOR: Splendid. Has anybody else gone down with the infection?
LIZ: Yes, Miss Dawson. She collapsed half an hour ago.
BRIGADIER: Yes, and the doctor and the nurse we saw at the hospital, and the ambulance man who took Baker there. Now has everyone here been inoculated?
LIZ: Yes, they've all been taken care of, except Doctor Lawrence. I can't find him anywhere.
DOCTOR: Yes, well, I'd be very happy to lose him. What about that chap from London, Masters?
LIZ: Haven't seen him either. Better go and find both of them.
(Liz leaves.)
BRIGADIER: Do you think we'll be able to contain this disease, Doctor?
DOCTOR: We may be able to contain it. The question is, can we cure it? Excuse me.
BRIGADIER: We were in contact with Baker. Does that mean that we're infected too?
DOCTOR: Can't be sure, Brigadier. We can't be sure of anything.
(The two lock gazes.)
BRIGADIER: Oh, I'll let you get on with it.
DOCTOR: Thank you.
(Liz bursts in.)
LIZ: Masters is gone.
DOCTOR: Gone where?
LIZ: He caught the London train. He must be nearly there by now.
BRIGADIER: Right, I'll get onto it. Maybe we can get him at the station. Will you come with me, Miss Shaw?
LIZ: Oh, I'm helping the Doctor.
BRIGADIER: I'll need help manning the phones.
LIZ: I am a scientist, not an office boy.
BRIGADIER: You're a member of UNIT, Miss Shaw, and you'll do as you're told!
LIZ: I will not be spoken to in that way!
DOCTOR: Liz.
LIZ: Doctor!
DOCTOR: Go with him, please. Anyone who's been in contact with Masters has got to be quarantined. He may spread that disease all over the country.
LIZ: Fair enough.

[Marylebone Railway station]

(Masters gets off the crowded train from the West Midlands at the farthest, and wipes his forehead. He walks down the platform, briefly coming over dizzy, then has to stand by the ticket collector whilst searching his pockets. He drops the ticket, picks it up and carries on through the concourse, feeling dizzy again. Outside the grand edifice he goes over to a taxi.)
DRIVER: Where to, sir?
MASTERS: Ministry of Science, please.
(The taxi drives off just as a police car hurtles into the station, sirens blaring.)

[Research Centre Laboratory]

(The scanning microscope is being set up by a pair of technicians.)
DOCTOR: Look, please hurry, this is very important, you know.
TECH: I'm being as quick as I can, sir.
(The Brigadier enters.)
BRIGADIER: Everything all right, Doctor?
DOCTOR: Yes, I think so. Now then, have they found Masters?
BRIGADIER: Not yet, they've sent a police car to the station.
DOCTOR: Yes, well, he's got to be found and put into quarantine at once.
BRIGADIER: Doctor, suppose I'm a carrier?
DOCTOR: No, I don't think you are. So far the antibiotics have held the disease in check. Have you finished? Good, splendid.
TECH: Yes.
DOCTOR: Thank you.
(The technicians leave.)
BRIGADIER: What do you think the Silurians will do now, Doctor?
DOCTOR: Well, it's hard to say really. I think they'll lie low for a while, and let the disease really get to work.
BRIGADIER: Well I've got men at all the cave mouths, and I've sent for reinforcements so we'll be ready for them if they do try anything.
DOCTOR: Brigadier, at all costs we must avoid a pitched battle.
BRIGADIER: You don't still think we can co-exist with the Silurians, do you?
DOCTOR: Well don't forget that one of them released me, which is giving us our only chance of defeating this disease.
BRIGADIER: Maybe one of the Silurians is friendly but the rest seem determined to wipe us out.
DOCTOR: Yes. Look, Brigadier, I've got a great deal of work to do!
BRIGADIER: Yes, of course.

[Silurian Control room]

SILURIAN JR: Remove the body. I am the leader now!
(Two Silurians carry the elder's corpse away.)
SILURIAN JR: I am the leader now.
(The scientist appears in the doorway.)
SILURIAN JR: Has the disease reduced the numbers of these apes?
SCIENTIST: Their resistance may be stronger. They may even develop a cure.
SILURIAN JR: The disease will be beyond the understanding of their science.
SCIENTIST: We cannot be sure.
(The scientist turns on the viewscreen and we see the Doctor at the microscope.)
SCIENTIST: That Doctor, the one who took the sample of bacteria, was a highly intelligent specimen.
SILURIAN JR: They're only apes. They will not develop a cure.

[Conference room]

(Liz is doing paperwork when Lawrence enters.)
LAWRENCE: Time hanging heavy on your hands, Miss Shaw?
LIZ: We're waiting to hear from London.
LAWRENCE: Oh, a matter of life and death, no doubt.
LIZ: Exactly that.
LAWRENCE: Where's the Brigadier?
LIZ: He's with the Doctor. The scanning microscope has arrived.
LAWRENCE: Oh, how pleasant to be able to obtain expensive pieces of scientific equipment so easily.
LIZ: Can I help you at all, Doctor Lawrence?
LAWRENCE: I doubt it. I have a complaint to bring to the Brigadier.
LIZ: A complaint?
LAWRENCE: Yes. My establishment has been brought to a complete standstill. My staff are suffering the ill-effects of a series of compulsory injections.
LIZ: You haven't had your own injections yet, have you?
LAWRENCE: No, nor do I intend to.
LIZ: But you've got to have them. It's for your own good.
LAWRENCE: Rubbish. Why should I waste my time having useless injections against an imaginary epidemic?
LIZ: Doctor Lawrence, it is quite clear that the disease exists. Major Baker is dead.
LAWRENCE: He may have been ill for some time. I should be interested to see the results of the post-mortem.
LIZ: Doctor Lawrence, you must admit there is a
LAWRENCE: I will admit nothing. There is no epidemic.
LIZ: Doctor Lawrence, please, listen to me.
LAWRENCE: You will excuse me, Miss Shaw.
(Lawrence leaves as the Brigadier enters.)
BRIGADIER: Now what's the matter with him?
(The telephone rings, and Liz hands it to the Brigadier.)
BRIGADIER: Lethbridge-Stewart? Yes. When? I see. All right, all right, I suggest you get on with it. Yes, I know London's a big place! The police just missed Masters at the station.
LIZ: Well, did anyone see him?
BRIGADIER: A ticket collector remembers someone who might have been Masters. Said he looked very ill. Anyway, he got a taxi and drove off.
LIZ: Well, then they're sure to find him.
BRIGADIER: Do you know how many taxis there are in London? And how many men who look more or less like Masters?

[Outside the Ministry]

(A police car, siren wailing, drives past as Masters gets out of the taxi.)
DRIVER: Seven and six, please, sir. Are you all right, sir?
(Masters hands over a pound note.)
DRIVER: You sure you're all right, sir?
(Masters walks away.)
DRIVER: Wait a minute, sir. You've forgotten your change, sir.
(Back at Marylebone, the ticket collector comes over faint for a few moments.)

[Caves]

(A private soldier is sitting on the ground, chewing gum and blowing bubbles. There is a crunch on the gravel nearby.)
WRIGHT: Who's that?
(He sits down again, and there is another noise.)
WRIGHT: Who's that?
(He uses his field telephone.)
WRIGHT: Wright, gallery five, over.
(A Silurian zaps him with its third eye. Wright's dying scream goes down the telephone to -)
HART: Come in, gallery five! Come in, gallery five! No good, sir. The line's gone dead.
HAWKINS: Well, what did he say?
HART: Just gave his name and the gallery number, sir.
HAWKINS: Then we'd better go in after him.
HART: Brigadier's orders were to stay here, sir.
HAWKINS: I want to know what happened to that man. Corporal!
NUTTING: Sir!
HAWKINS: Take over here. Come along, Sergeant! (Near gallery five.)
HART [OC]: Wright! Wright!
(The Silurian hides.)
HART: Wright!
(Hart and Hawkins find Wright sprawled over a rock. The Silurian appears and zaps Hart. Hawkins takes cover and shoots at it.)

[Silurian Control room]

(Junior operates the monitor.)
SILURIAN JR: Look! Soldiers are guarding the exits from the caves.
SCIENTIST: Perhaps the humans can resist the bacteria.
SILURIAN JR: We must recapture the one that took the sample. Without him, the others will die from the disease.
SCIENTIST: Come with me.

[Research Station laboratory]

(Trays of sample bottles are brought in.)
DOCTOR: That's excellent, thank you.
LIZ: That's quite a collection.
DOCTOR: One of those drugs, maybe a combination of them, will probably cure this disease. The question is, which?
LIZ: Where are you going to start?
DOCTOR: By finding out more about that bacterium. I've already analysed it, but I need to know more about its effect. Can you get me a blood specimen from someone who's been infected?
LIZ: Yes, of course.
(Liz leaves.)
DOCTOR: I only hope I shan't be too late.

[Marylebone Railway station]

(People are collapsing, with lesions on their faces. An ambulance arrives, startling the pigeons, to a scene of people on the ground and more falling every moment.)
TANNOY: Attention please! Attention please! This is a police message. Stay where you are. Do not attempt to leave the station. If you feel ill, assistance will be brought to you. Attention, please! Attention, please! This is a police message. Stay where you are. Do not attempt to leave the station. If you feel ill, assistance will be brought to you.
(As more people collapse, the Brigadier makes telephone calls, the Doctor works and Liz gets the blood sample he needs. Masters staggers up from an underpass with very bad marks on his face. There are police running after him. He collapses against railings and dies just as they get to him.)

[Research Station laboratory]

LIZ: Here's the blood specimen.
DOCTOR: Good, splendid. Who did you take it from?
LIZ: That ambulance man you had brought back to the sick bay.
DOCTOR: Oh. How is he?
LIZ: Getting worse. How are you getting on?
DOCTOR: I've no idea. We may be getting somewhere now, though.
(The Doctor puts a drop of infected blood onto three slides.)
LIZ: They've sent you just about every drug in existence. Surely there must be something?
DOCTOR: My dear girl, some of these drugs are so new they don't even know their properties yet.
(He adds a drop of solution to a slide and puts it under the microscope.)
DOCTOR: Right. Here goes.
(They look at the results on the monitor.)
DOCTOR: No, that's no good. Let's try the next one.

[Conference room]

(The Brigadier is on the telephone.)
BRIGADIER: The Doctor and Miss Shaw have been working flat out for a very long time. They're tackling an immensely difficult task under conditions of great pressure and I do not propose to make it worse for them by breathing down their necks. Excuse me, will you?
(The Brigadier answers a second telephone.)
BRIGADIER: Will you hold on please?
(And back to the first.)
BRIGADIER: Yes, of course I'll let you know as soon as I get any result that's at all positive. Goodbye.

[Research Station laboratory]

(Liz is onto the third page on her clipboard.)
DOCTOR: No, that's no good. You know, I'm beginning to lose confidence for the first time in my life. And that covers several thousand years.
LIZ: Well, at least you've narrowed it down to forty possible drugs. Have you considered the addition of A thirty seven in the presence of Z nineteen might well be effective?
DOCTOR: Yes, that's a possibility. Let's try.
(They prepare another slide, and just as the Doctor puts it under the microscope, Liz sways, bumping into him.)
DOCTOR: Liz, watch what. You all right?
LIZ: Sorry. I feel dizzy.
DOCTOR: Yes, well, I expect those antibiotics are wearing off. You'd better get down to the sick bay and have another jab.
LIZ: What about you?
DOCTOR: I'm all right.
LIZ: Oh, come on, Doctor, I think you
DOCTOR: Liz, I am all right!
(A crowd gathers to watch Masters being taken away on a stretcher.)

[Conference room]

(Another telephone call.)
BRIGADIER: Yes. Could hardly be worse, could it? Right.
(Liz enters as he puts down the phone.)
LIZ: Who was that?
BRIGADIER: The Ministry.
LIZ: Masters?
BRIGADIER: He's dead. Outbreaks of the disease are being reported all over London.
(Even the Doctor is starting to feel dizzy now. Lawrence bursts in, lesions on his face.)
LIZ: Doctor Lawrence! His face!
BRIGADIER: Doctor Lawrence, you really must report to the isolation ward at once.
LAWRENCE: I've had enough of you.
BRIGADIER: I really must insist, sir! You're endangering all of us!
LAWRENCE: Insist! Oh, you do insist?
BRIGADIER: Now listen, sir
LAWRENCE: Before you people came, I was director of an important research establishment. Now the place is shut down, my career's in ruins, and you are to blame!
BRIGADIER: Oh you're talking absolute nonsense.
LIZ: Don't argue with him. I'll go and get one of the medical orderlies.
(Lawrence stops Liz from leaving.)
LAWRENCE: You think I don't know what's going on, don't you?! This whole business has been a plot to get rid of me.
BRIGADIER: Oh really, Doctor Lawrence.
LAWRENCE: You think? I know I've got enemies in the Ministry. Even Masters!
LIZ: All right, Doctor Lawrence. We want to help you.
LAWRENCE: Well, you can clear out of here, all of you. And take that crazy Doctor with you! And all of your military rubbish! I'm in charge of this place! Well, are you going? Or do I have to throw you out myself!
(Lawrence leaps over the table to start throttling the Brigadier. He is pushed off, suddenly stands still, clutches his chest and falls.)
LIZ: He's dead.

[Research Station laboratory]

(The Doctor checks another slide under the microscope.)
DOCTOR: Eureka!

[Conference room]

(Still more telephone calls.)
BRIGADIER: All right, thank you. Bad news, Miss Shaw. The first one abroad. Paris.
LIZ: If we can't contain it in Britain, what chance has the world got?
BRIGADIER: If only we'd prevented Masters from leaving here!
(The Doctor enters.)
DOCTOR: I think I've found it.
BRIGADIER: You've found the antidote?
DOCTOR: Well, it works in the laboratory. Now let's see whether it works in practice.
(The Brigadier picks up a phone.)
BRIGADIER: Hello? Get me Doctor Crawford.

[Silurian Base]

SCIENTIST: This is the closest point to the human's base.
SILURIAN JR: Then we will penetrate from here.
(They start to burn through the rock with their third eyes.)

[Sickbay]

DOCTOR: You wanted to see us, Liz?
LIZ: Yes, his temperature's dropped, and his pulse is normal.
DOCTOR: That's excellent, excellent! Yeah, there's a good chap. That's it. Now you'll want to telephone that formula to London. I'll go and write it out for you straight away.
LIZ: Thank you.
(The Doctor leaves.)
BRIGADIER: Will the medical team be able to mass produce enough in time?
LIZ: Well, they've been standing by for hours. All they need is the formula.
BRIGADIER: I'll get a line open to them.
(Hawkins enters.)
HAWKINS: Sir, the Silurians have killed Sergeant Hart.
BRIGADIER: Any sign of a major attack?
HAWKINS: Yes, they've broken out of their base and are advancing everywhere.
BRIGADIER: Right.

[Conference room]

(The phone is ringing as the Brigadier and Liz enter.)
BRIGADIER: Lethbridge Stewart? The Daily what? How did you get hold of this number? Look, I have no comment to make. Now will you please get off this line. What's keeping the Doctor?
LIZ: You leave him alone. He's got a complicated formula to transcribe.

[Research Station laboratory]

(The Doctor pauses writing the formula as he thinks he can hear something. Behind him the wall beyond the open door starts to glow red, then two Silurians walk through the hole and use their third eyes on him.)

Episode Seven

[Conference room]

BRIGADIER: And there's no news from cave mouth two?
UPTON: We've lost contact with cave mouth two, sir.
BRIGADIER: Well, I want reports from all sectors as they come in, and get me Captain Hawkins.
UPTON: Sir!
(Upton leaves as Liz enters.)
LIZ: I've checked on the ambulance man in the sick bay. The discolouration of the skin is fading rapidly.
BRIGADIER: So the Doctor's antidote seems totally effective?
LIZ: So far, yes.
BRIGADIER: I wish he'd get a move on with that formula!

[Research Station reception]

(The unconscious Doctor is being dragged out of the laboratory by the Silurian scientist, when Upton comes round the corner.)
UPTON: Sergeant!
(Junior gives him the third eye treatment.)
SILURIAN JR: Quickly! There may be others.
(The Silurians go through the hole they made in the wall, then Junior seals it up again.)

[Conference room]

(Both the Brigadier and Liz are fielding phone calls.)
BRIGADIER: Hold them long as you can. I'm doing my level best to get you the support you need.
LIZ: UNIT control?
BRIGADIER: Over and out.
LIZ: Yes, Doctor Crawford.
BRIGADIER: Crewcock, bring that down here.
LIZ: I know. Look, I'm terribly sorry.
BRIGADIER: Look, what's happening about my call to the Ministry of Defence?
LIZ: Well I'm sure the Doctor won't be much longer.
BRIGADIER: Well, look, hurry it up, man. This is top priority!
LIZ: I do realise. All right. Goodbye.
(They put their phones down.)
BRIGADIER: Trouble?
LIZ: Doctor Meredith is getting very impatient.
BRIGADIER: I can't say I blame him.
LIZ: Give the Doctor a couple more moments. I mean, he may have run into some kind of problem.

[Research Centre reception]

(Hawkins steps out of the lift and sees Upton's body on the floor. He draws his revolver, then goes over to the 'repaired' hole in the wall. A scientist enters.)
HAWKINS: Hey, you. Give me a hand. Well, don't stand there gawping, man! Come on, give me a hand!

[Conference room]

BRIGADIER: Yes, all right, Major Walton. Pull back from gallery four and try and hold them at cave mouth three.
(LIZ answers another phone.)
LIZ: UNIT control?
BRIGADIER: Over and out.
LIZ: Yes, sir, he's here. Hold the line. The Ministry of Defence.
BRIGADIER: Miss Shaw, I must have that formula.
LIZ: All right. I'll go and see what's holding the Doctor up.
(Liz leaves.)
BRIGADIER: Lethbridge-Stewart here, sir. You got my message? With respect, sir, I don't think you appreciate the gravity of the situation. But there's no time to refer it to the Defence Committee.

[Research Station laboratory]

(Liz glances at the mark on the wall before entering the lab.)
LIZ: Doctor, the Brigadier
(Liz steps on broken glass and picks up a large piece of it together with a crumpled piece of paper, then gathers up all the other papers on the bench and runs.)

[Conference room]

(The Brigadier is part way through another phone call.)
BRIGADIER: But where is he?
LIZ: I've told you. I've no idea.
BRIGADIER: You'll read the formula to Doctor Crawford. He's been hanging on long enough.
LIZ: Don't you understand? I don't know which is the formula.
BRIGADIER: Hello, Doctor Crawford? Look, I'm afraid I'll have to ring you back. There's been yet another delay. Yes, yes, yes, as soon as I can.
LIZ: Brigadier, there was some glass in the lab. I don't know if there's
(Hawkins enters.)
HAWKINS: Sir! Sir, there's been some kind of a raid. Private Upton's dead.
BRIGADIER: In the caves?
HAWKINS: No, sir, here. Just down the corridor. And there's a kind of scorch mark on the wall.
BRIGADIER: Stay here, Miss Shaw.
LIZ: What?
BRIGADIER: Stay here!
LIZ: Yes, of course.
(Liz sorts through the papers, then smoothes out the crumpled piece and smiles. She picks up the telephone.)
LIZ: Get me Doctor Crawford, please.

[Silurian cages]

SCIENTIST: How many humans have survived the epidemic?
DOCTOR: They will all survive.
SILURIAN JR: That is impossible!
SCIENTIST: You have discovered a cure?
DOCTOR: Yes, and soon all the humans will be immune to your epidemic. Your plan has failed, as your leader wanted it to fail.
SILURIAN JR: Our leader is dead. I killed him. I am the leader now.

[Conference room]

LIZ: Thank you, Doctor Crawford.
(The Brigadier and Hawkins enter.)
BRIGADIER: The Silurians have broken in.
LIZ: Well, what about the Doctor?
BRIGADIER: Well, I imagine they've taken him to their base. Captain Hawkins, send every man we've got into the caves, and I want all civilian personnel evacuated from here immediately.
HAWKINS: Sir.
BRIGADIER: And organise a thorough search of that laboratory.
HAWKINS: I'll see to it myself, sir. You two, come with me.
(Hawkins and the soldiers leave.) 
LIZ: I've given the formula to Doctor Crawford. They're going to make their own tests and then go into mass production of the antidote.
BRIGADIER: Well done, Miss Shaw.
LIZ: What are you going to do about the Doctor?
BRIGADIER: What can I do?
LIZ: Try to rescue him! You'll have to attack their base.
BRIGADIER: At the moment, they seem to be attacking us.

[Silurian cages]

(The sound of the UNIT gunfire is close by.)
SILURIAN JR: Since the epidemic has failed, we must use other means. We intend to make this planet uninhabitable for humans beings.
DOCTOR: But you can't do that! You can't exterminate a whole species.
SILURIAN JR: Is the disperser ready for activation?
SCIENTIST: All we need now is the power.
SILURIAN JR: We shall continue to use the electricity of the humans.
DOCTOR: I'm afraid you won't be able to do that. Thanks to you, the humans are no longer making power. Their generator has been switched off.
SCIENTIST: Then you will help us.
SILURIAN JR: We shall force you to reactivate it. We shall take the centre!

[Conference room]

(The Brigadier is trying to make a telephone call.)
BRIGADIER: Hello? Hello? Hello? Switchboard? What's the matter with this thing?
(The lights dim and the aircon slows.)
BRIGADIER: What the devil?
LIZ: We seem to have switched to an emergency lighting system.
(She tries another phone.)
LIZ: Hello? It's dead.
(They wind the field telephone.)
BRIGADIER: This one's dead too. And I've just sent the last of my men into those caves.
LIZ: What do you mean?
BRIGADIER: Because of the attack, I sent every man I've got down to the caves and now the Silurians are cutting our communications.
LIZ: What about your pocket radio?
BRIGADIER: No, useless at this depth.
LIZ: If they could break in once to get the Doctor, they could break in again.
BRIGADIER: Exactly. Only this time it'll be in force.

[Silurian hibernation room]

(The Scientist is using his third eye on a casket, with no success.)
SILURIAN JR: Is the machinery prepared?
SCIENTIST: I could do nothing without power from the human's generator. It has ceased to function.
SILURIAN JR: We shall force them to reactivate it. When your instruments register the power, you will revive all our people. Now, I shall take the one called the Doctor to the research centre.

[Research Centre reception]

BRIGADIER: I'll go to the Ministry myself. We need a division down here and I'll see we get it.
(The Brigadier tries to summon the lift.)
BRIGADIER: What's the matter with this thing?
LIZ: The telephone's stopped working.
BRIGADIER: Now the lift as well.
(The scorch mark in the wall begins to glow.)
LIZ: Brigadier, look!
(The hole reappears and the Doctor walks through.)
LIZ: Doctor!
(Followed by Silurians.)
SILURIAN JR: Put down that weapon!
(In the laboratory opposite the hole, Hawkins can hear everything as he hides behind the open door.)
DOCTOR: Do as he says, Brigadier, or they'll kill us all.
SCIENTIST: We do not need these humans.
DOCTOR: Miss Shaw is a scientist. If I am to do what you want, I shall need her help.
SILURIAN JR: The other one is a soldier. He is dangerous. Kill him!
(One Silurian starts to use its third eye. Hawkins steps out of the lab and shoots. The Doctor is grabbed as a shield.)
DOCTOR: Stop!
LIZ: Brigadier!
DOCTOR: No!
(Hawkins falls to the ground.)
DOCTOR: Any more killing I shall refuse to help you! You'll have to kill me too!
SILURIAN JR: You will take us to the nuclear generator or we will kill you all!
DOCTOR: Very well. I'll do as you want.

[Cyclotron room]

(A Silurian bursts in and uses its third eye on the scientists.)
DOCTOR: Stop! Stop! I said there was to be no more killing! Stay where you are! This centre is now in the hands of the Silurians. They need the use of the generator. Now if you follow carefully the instructions, I shall give you, your lives may be spared.
SILURIAN JR: Remove the bodies.
BRIGADIER: Doctor, what do you think you're doing?
DOCTOR: Trying to save your lives. Now keep out of the way and keep quiet.
SCIENTIST: You will now connect this device to the nuclear generator.
DOCTOR: The power source is over here.
(A large contraption with a dish on top is wheeled in.)
DOCTOR: What is the purpose of this machine?
SILURIAN JR: That is no concern of yours.
DOCTOR: If I'm to help you, I must know.
SCIENTIST: This is the molecular disperser. It will convert the energy of the nuclear reactor into microwaves.
DOCTOR: Oh, for what purpose?
SCIENTIST: The microwaves will disperse the molecules of the filter belt which has enveloped this planet since our time.
DOCTOR: But if this process gets out of hand, it will destroy all life on the planet.
SCIENTIST: We can control the process. Commence work!
BRIGADIER: (sotto) What are they going to do?
LIZ: (sotto) Destroy the Van Allen belt.
BRIGADIER: (sotto) What?
LIZ: (sotto) The Van Allen belt. It surrounds the planet and filters out some of the sun's radiation.
BRIGADIER: (sotto) What happens when it's gone?
LIZ: (sotto) It gets so hot, we will all die of sunburn on a cloudy day.
BRIGADIER: (sotto) What good will that do them?
LIZ: (sotto) They're reptile, cold blooded. They'll thrive in heat. We shall die. It'll mean the end of the human race.

[Silurian hibernation room]

SILURIAN: The generator of the humans is producing power. Commence the revival process.
(A casket starts to open, but the Silurian inside cannot sit up. The lid falls back.)
SILURIAN: The power is still too low.

[Cyclotron room]

SCIENTIST: You will now provide power to operate the de-hibernation machinery and activate the disperser.
DOCTOR: Yes, well, we'll need to stoke up the reactor. Miss Shaw, I'll need your help, please.
BRIGADIER: You mustn't help him.
LIZ: The Doctor knows what he's doing. Trust him.

[Cyclotron control room]

(The Doctor is at the control desk, with Junior watching.)
DOCTOR: Miss Shaw, I want you to feed uranium into the reactor, all right?
(Junior moves away.)
DOCTOR: (sotto) When I tell you, lower all the rods in at once.
LIZ: (sotto) Doctor, that will
DOCTOR: Liz, I know what I'm doing. Please do as I say.
(Liz goes back into the cyclotron room and the Doctor speaks into the microphone.)
DOCTOR: All technicians to your usual sectors, please. To your usual sectors, please. All right, Liz?
LIZ: [OC] Yes.
DOCTOR: Lower in number one rod.
LIZ [OC]: Number one rod. Check.
DOCTOR: Lower in number two rod.

[Cyclotron room]

LIZ: Number two rod. Check.
DOCTOR [OC]: Sector one, increase your power level. Lower in number three rod.
LIZ: Number three rod. Check.

[Cyclotron control room]

DOCTOR: Now you should be getting enough power now to get your disperser unit into operation.
(The dish antenna starts to pulse.)
SILURIAN JR: Continue to increase the power.
DOCTOR: As you wish. Liz, now!
(The megawatts meter leaps from 1.2 past the end of the red zone. The disperser goes Bang!)
SILURIAN JR: You have destroyed the disperser!
DOCTOR: Yes, I know.

[Cyclotron room]

SILURIAN JR: Turn off the reactor!
SCIENTIST: Remove the uranium from the reactor.
(The scientist pushes Liz towards a control panel.)
DOCTOR [OC]: Liz, keep away from those controls! Get back!
(The panel goes bang as Liz runs back to the desk.)
DOCTOR [OC]: The reactor is now permanently overloaded.

[Cyclotron control room]

DOCTOR: There's going to be a massive explosion, and a colossal radiation leakage.

[Cyclotron room]

BRIGADIER: The whole area will become deadly.
SILURIAN JR: For how long?
LIZ: A quarter of a century, possibly more.
SCIENTIST: This means nothing to us. We shall return to our base and wait in hibernation until the radiation has faded.
SILURIAN JR: Kill these humans!
SCIENTIST: No! They will all stay here to die from the radiation.
(The Silurians leave.)

[Cyclotron control room]

BRIGADIER: Well done, Doctor.
DOCTOR: Well done, Brigadier.
BRIGADIER: Well, hadn't you better close down the reactor?
DOCTOR: I can't.
BRIGADIER: You were surely bluffing them?
DOCTOR: Well, I exaggerated a bit, but I had to push the reactor past the critical stage or they'd never have believed me. We'd better get out of here at once.
BRIGADIER: We can't.
DOCTOR: Why not?
BRIGADIER: They've jammed the lift. There's no way out.

[Silurian hibernation room]

(The scientist uses his third eye to push a casket across the floor.)
SCIENTIST: The re-hibernation mechanism is defective. One of us must remain.
SILURIAN JR: I am the leader. The responsibility is mine.
SCIENTIST: The one who remains here will die.
SILURIAN JR: Is sufficient power stored in the hibernation unit?
SCIENTIST: Yes, I have set the controls to revive us in fifty years from now.
SILURIAN JR: When our people revive, you will be the leader. See that the apes are destroyed.

[Cyclotron control room]

(The power meters are still in the red as the Doctor works on a bundle of wires under the desk.) 
BRIGADIER: Any good now?
LIZ: No, it's still not working.
DOCTOR: Give me time, Liz, give me time. There you are. Try that now.
LIZ: The mega-wattage is still rising.
DOCTOR: Yes, I know. I'll try fusing the control of the neutron flow. Now stand well back and cover your eyes.
(The Doctor adjusts controls on the desk then joins the Brigadier and Liz at the back wall. Bang! Flash!)
DOCTOR: Well, that seems to have done it.

[Silurian hibernation area]

(The Doctor has come potholing again.)
SILURIAN JR: You are still alive. You tricked us!
DOCTOR: I managed to close down the reactor.
SILURIAN JR: Then the others must be revived at once. But first, I shall kill you.
(Junior uses his third eye. The Brigadier runs in and shoots him down, eventually.)
BRIGADIER: Doctor!
DOCTOR: Well done, Brigadier. Now then
BRIGADIER: And just what do you think you're doing down here?
DOCTOR: I'm trying to find out how this hibernation unit works. I must know if we're going to revive them again.
BRIGADIER: Revive them?
DOCTOR: Yes, not all at once, you understand. One at a time, so that we can reason with them. There's a wealth of scientific knowledge down here, Brigadier, and I can't wait to get started on it.

[Cyclotron control room]

DOCTOR: Yes, well, everything seems to be working quite smoothly. I don't think they'll be any more trouble.
BRIGADIER: Splendid.
DOCTOR: Now, don't forget, Brigadier, nobody is to go into that Silurian base.
BRIGADIER: Yes, Doctor.
DOCTOR: Miss Shaw and I will be back as soon as possible with some testing equipment and probably some other scientists.
BRIGADIER: Good, good. Well, have a good journey.
DOCTOR: Yes. Don't forget, Brigadier. Nobody is to go into that base, all right? I'll see you tomorrow.
LIZ: Goodbye.
BRIGADIER: Goodbye, Miss Shaw.
LIZ: Thank you.
(The Doctor and Liz leave.)
BRIGADIER: Corporal Nutting?
NUTTING: Sir?
BRIGADIER: Everything set up?
NUTTING: Yes, sir.
BRIGADIER: Give them time to get clear, and then set off those explosive charges. I want that Silurian base sealed permanently.
(Junior is not quite dead. It drags itself over to a casket and starts using its third eye.)

[Wenley Moor]

(Bessie is sulking in the middle of the moor.)
LIZ: Shall I walk back and get some help?
DOCTOR: No, no. No, it's just a minor technical fault. We'll soon put that right.
(The Doctor pours a small vial of red liquid into the radiator. He counts off a few seconds on his watch, Bessie gurgles and the Doctor traces a path through her workings with his finger until the liquid dribbles out of the exhaust pipe on cue and she starts up.)
DOCTOR: There you are. That's fixed it.
(Boom, and it isn't Bessie back-firing.)
LIZ: What's that?
(There is an explosion on the moor. Underground, Junior flails around. More explosions.)
DOCTOR: The Brigadier. He's blown up the Silurian base.
LIZ: He must have had orders from the Ministry.
DOCTOR: And you knew?
LIZ: No! The government were frightened. They just couldn't take the risk.
DOCTOR: But that's murder. They were intelligent alien beings. A whole race of them. And he's just wiped them out.
LIZ: I know.
(To a background of primary and secondary explosions, they drive away.)