In trying to retrieve the clones from inside the Doctor, the alien virus is brought from the microbial world into the macro-world, and it's ready to spawn.
THE INVISIBLE ENEMY BY BOB BAKER AND DAVE MARTIN Part Four Running time: 21:22 [SCENE_BREAK] NUCLEUS: Help me out. DOCTOR: Professor Marius. The Doctor sees Marius' scaly face. DOCTOR: Oh no, not you too. MARIUS: Yes, Doctor. Contact has been made. Now I serve the purpose. DOCTOR: What? That pathetic crustacean, your leader? MARIUS: You are speaking of the Nucleus, the Nucleus of the Swarm. NUCLEUS: Take me to him. DOCTOR: Finding the macro world difficult? NUCLEUS: It suits me well. DOCTOR: I thought I'd got rid of you. NUCLEUS: You were mistaken. I made use of your escape route through the eye. DOCTOR: Yes, you'd have known about that, wouldn't you. NUCLEUS: Another mistake, and a costly one, Time Lord, because now, thanks to your dimensional stabiliser, I am no longer forced to exist in the micro world to breed and multiply. My Swarm, when it is hatched on Titan, will no longer be invisible microbes prey to all, but mighty and invulnerable creatures, invincible. The age of man is over, Doctor. The age of the virus has begun. DOCTOR: I've heard it all before. You megalomaniacs are all the same. NUCLEUS: Bring him with us to Titan, to be consumed by the Swarm. [SCENE_BREAK] In another room Leela has dressed in the green PVC nurses outfit and puts makeup on her face to look as if she's possessed by the virus. LEELA: How do I look? K9: Friend, mistress. LEELA: If I can just get close enough to that Nucleus, we'll see how friendly I am. K9: Hostiles approaching with the Doctor. Out in the corridor the infected people are moving the nucleus and the Doctor toward the airlock. LEELA: Come on. NUCLEUS: Hurry, hurry. It is time for the spawning. I must get to the place prepared on Titan. MARIUS: Nurse, take over here. I must assist the Nucleus. NUCLEUS: Hurry! MARIUS: Come with me. NUCLEUS: Breeding time approaches. They reach the airlock. Leela continues pushing the Doctor's gurney past them - she has already cut the bonds. MARIUS: Nurse, not that way. The Doctor leaps off the gurney. Leela takes cover and pulls her blaster. MARIUS: Stop them! The Doctor hurls the gurney at Lowe. There is a brief exchange of blaster fire. LOWE: They're getting away! NUCLEUS: No, they are simply trapped. NUCLEUS: Marius, stay here to make sure the Doctor doesn't escape, and make contact with all other staff in the Foundation. Bring the Doctor to us later. Hurry! [SCENE_BREAK] Inside the TARDIS Leela removes her makeup and hat. LEELA: Now what? DOCTOR: Now nothing. LEELA: Doctor, if we get to Titan first, we can still beat that thing. DOCTOR: No, we can't. The dimensional stabiliser's still in the isolation ward. Without it, the TARDIS won't move an inch. LEELA: You mean there's nothing we can do? DOCTOR: I didn't say that. He crouches down. DOCTOR: K9. Now listen to me, K9. Do you think you could poleaxe, do you think you could poleaxe Marius? K9: Poleaxe? DOCTOR: Yes, knock him out. K9: Affirmative. My photon beam weaponry has four levels of intensity, Doctor. Kill, paralyse DOCTOR: No, no, no, not kill. Not kill. Just knock out. K9: Affirmative. DOCTOR: Good dog. K9 rolls out of the TARDIS doors. [SCENE_BREAK] Marius is waiting outside using the intercom. MARIUS: All senior staff, report to Reception. This is Professor Marius speaking. All senior staff report to Reception. Ah, K9. K9, I no longer require you to obey... K9 blasts him. The Doctor comes out. DOCTOR: You're a good dog, K9. Good dog. [SCENE_BREAK] We see the base in space. Damage from the shuttle crash is NOT clearly visible. Next we see the exhaust pipes of a shuttle flaring into life. The shuttle on the pad lifts off. It flies away from the base. [SCENE_BREAK] Back in the lab they've got Marius lying on the table. DOCTOR: Come on, Leela, quickly. We haven't got a moment to spare. Not frightened of blood, are you? You, the mighty huntress. LEELA: Just hurry up. LEELA: Haven't we been through all this before? DOCTOR: I had a virus then. I'm immune now. Something must have happened while you and I were inside my head. I want to find out what. Ah, that's interesting. You see that? He puts the sample up on the monitor screen. DOCTOR: That little fish hook is the only thing that you and I have in common. It wasn't there before, so it must be the antibody, the immunity factor. LEELA: How did what I have get into your bloodstream? DOCTOR: Quite simple. Your clone was absorbed into my bloodstream and passed on the immunity to me. All we've got to do is isolate it, analyse it, duplicate it and inject it into Marius here, and he in turn will be able to cure all the others. LEELA: What about the Nucleus? What about Titan? DOCTOR: Come on, one thing at a time. One thing at a time. [SCENE_BREAK] On board the shuttle. NUCLEUS: Faster, faster. LOWE: We can't. We'll burn out the motors. NUCLEUS: Let them burn out. Once we reach Titan and the breeding tanks, our job is finished. LOWE: What about the Doctor? NUCLEUS: He will follow. Marius will make sure of that, whatever happens. Faster. Use all the fuel. Faster! Lowe pushes the controls to maximum. [SCENE_BREAK] Back in the lab. LEELA: Doctor, look! It's working. The scales fade from Marius' face. DOCTOR: Sometimes my brilliance astonishes even me. Come on, Marius. Wake up, wake up. Come on. MARIUS: Where's Parsons? What happened? DOCTOR: He's dead, I'm afraid. Do you remember anything? MARIUS: I remember Lowe coming in, and then Parsons, and then a flash and then nothing. Did the experiment work? DOCTOR: Yes and no. Unfortunately the Nucleus got away by means of the dimensional stabiliser. It's on its way to Titan to breed. MARIUS: Was I taken over? DOCTOR: Yes, it got to you. MARIUS: But we found the immunity factor, so we're safe here for a while. What was it? DOCTOR: It was something in Leela. Something we all missed. This is it. You'll have to cultivate a great deal more. MARIUS: Yes. DOCTOR: If those antibodies can confer immunity, they can be used to attack the Nucleus. MARIUS: Attack the Nucleus? Oh, that's dangerous. DOCTOR: Of course it's dangerous. If we allow the Nucleus to breed and swarm, it'll go through the entire Solar System like a plague of giant locusts. MARIUS: But will you get to Titan on time? DOCTOR: Yes, by means of the dimensional stabiliser. [SCENE_BREAK] On Titan Safran calls the shuttle. SAFRAN: Safran on Titan. Safran on Titan. The hive is prepared. The breeding tanks are ready. Temperature and humidity are set. I await your arrival from the generation of the Swarm. [SCENE_BREAK] Back on board the shuttle. LOWE: Maximum speed. We have reached maximum speed. NUCLEUS: Faster! We must go faster! Now the time for spawning is very close. Lowe pushes the controls further. [SCENE_BREAK] Back in the lab, Marius and others are working. LEELA: How much longer? DOCTOR: We can't rush these things. They're breeding as fast as they can. K9 will tell us when they've got the most powerful strain. LEELA: Doctor, why don't we just blow up Titan? Nucleus, breeding tanks, everything. DOCTOR: That's your answer to everything, isn't it, knock it on the head. LEELA: Effective, isn't it? Smash it once and for all. Well? DOCTOR: With what? This is a hospital, not an arsenal. LEELA: All right, what are you going to do? K9: Confirm. Confirm strain C five three one has lethal capacity. MARIUS: Doctor, we've done it! Congratulations. There isn't a moment to be lost. Cultivate C five three one. DOCTOR: Thank you, K9. LEELA: And? DOCTOR: Now, just get it into the tanks and wait for it to attack the Nucleus in the same way it attacked us. Microscopically. It's neat, don't you think? LEELA: Is that all? If we can get to Titan on time, if we can get past Lowe and the others, if it works when we get it in there. If. I thought you didn't like killing? DOCTOR: I don't. LEELA: Then why are you doing all this? DOCTOR: The virus has a perfect right to exist as a virus, not as a giant storm threatening the entire Solar System. Everything has its place. Otherwise the delicate balance of the whole cosmos is destroyed. LEELA: I still say we should blow it up. MARIUS: Doctor. The batch is complete. DOCTOR: Good. Now for the TARDIS. [SCENE_BREAK] Lowe's party with the nucleus has reached Titan. NUCLEUS: Remember, I must be protected in the hive. The future of the Swarm depends on you now. They place it into the tank. [SCENE_BREAK] Back at the reception area Leela and the Doctor are going into the TARDIS, Marius and K9 nearby. MARIUS: Good luck, Doctor. DOCTOR: Thank you, Professor. Oh, Professor. MARIUS: Yes? DOCTOR: I don't suppose we could borrow K9, could we? MARIUS: Borrow K9? DOCTOR: Shush. MARIUS: What for? DOCTOR: Well, I'm not at liberty to say, but he could be very useful. MARIUS: Of course. I understand. K9, obey the Doctor. K9: Affirmative. He rolls toward the TARDIS but doesn't actually go in on camera because it's physically impossible for him to do so. [SCENE_BREAK] Back on Titan, Lowe and the others take up defense positions. Lowe looks into the chamber where the nucleus writhes. Inside the breeding tank, bulbous things pulsate. In the supervisor's office, Safran is watching the hive on the monitor. He hears the TARDIS noise and leaves the room. The TARDIS materializes inside. The Doctor emerges, heads to the door, then comes back to look at the television monitor. LEELA: Doctor, what is it? DOCTOR: They're starting to hatch. Outside the door, a guard holds his blaster ready, listening intently. DOCTOR: Let's go. He opens the door and immediate ly slams it shut again. LEELA: Now what's the matter? DOCTOR: There's a man at the door. Leela waves the Doctor aside, crouches and aims her blaster at the door. There is a knock. DOCTOR: Come in. Leela fires at the guard. He strides forward mostly unaffected. But as he moves toward Leela, K9 fires and the guard falls to the ground. LEELA: Thank you, K9. Well, Doctor, what's wrong? Why didn't my blaster work? DOCTOR: They're developing a resistance to radiation. Their internal cell structure K9: Problem. I have a problem. Offensive capability seriously diminished. Reserves very low. LEELA: K9's breaking up, my blaster's finished. What are we going to do? DOCTOR: Shall we try using our intelligence? LEELA: Well, if you think that's a good idea. DOCTOR: Come on. The breeding of bulbous things continues. [SCENE_BREAK] In the corridor outside. DOCTOR: (quietly) K9, do you see that guard? K9: (quietly) Affirmative. DOCTOR: (quietly) I want you to decoy him. He pats K9 on the head, and K9 rolls forward. The guard follows and we hear blaster fire. Lowe and Safran are viewing the nucleus. K9 returns. K9: Mission accomplished. DOCTOR: Good dog. Your turn now, Leela. See you back at the TARDIS. LEELA: Or not. Good luck, Doctor. You know we should have done what I said. DOCTOR: What was that? LEELA: Blow them up. Goodbye, Doctor. She runs off. K9 comes down the corridor. Safran runs past, and Lowe fires continuously at K9 as he rolls onward. The Doctor approaches the hive. Lowe wasn't dumb - he wasn't drawn off. He aims his blaster at the Doctor. LOWE: Your futile attempt has failed, as we knew it would. Now you will join the Nucleus. DOCTOR: Well, I'd rather not, actually. LOWE: You have no choice. DOCTOR: Oh look, look, they appear to be hatching. Are congratulations in order? Lowe opens the door to the hive. LOWE: You will join the Swarm to be consumed, to become part of our purpose! K9 blasts him from behind, and the Doctor pushes Lowe into the hive. DOCTOR: Well done, K9, well done. Come on. Let's get out of here while there's still time. K9: I cannot. All reserves finished. DOCTOR: What? Come on. He quickly attaches a lead to K9's neck. DOCTOR: Come on. He strides quickly from the spot, pulling K9 on the lead. NUCLEUS: Come back, Doctor. We need you. Leela walks past an oxygen tank and onto a raised platform. You can see her underwear. Safran is hunting her and comes in below the platform. If he'd look up he'd have a great view. She leaps down onto him and they fall to the floor. Without much effort, she stabs him in the neck. The Doctor and K9 enter. LEELA: Did you kill it? DOCTOR: No, I lost the antibodies. LEELA: What? Never mind, Doctor, I've found the answer. DOCTOR: You have? LEELA: Knife them in the neck. DOCTOR: Can you do that to a thousand? A thousand thousand? LEELA: What are we going to do? Tom flubs his line here which should be "I think I've got an idea". DOCTOR: That's a good idea. Take K9 back to the TARDIS. He's out of juice. He sees the oxygen tank and goes up on the raised platform. He looks at the controls. He moves from the platform to the door of the hive. He attaches something to the door handle. NUCLEUS (OOV.): Who's there? He comes around to the side of the hive tank and turns a wheel. He pulls a hose from the side. NUCLEUS (OOV.): Is that you, Time Lord? DOCTOR: Well, as far as I know, there's no one else except you and me here, so it must be me. He attaches a wire to the door handle. Leela pulls K9 down the corridor. The exhaust spews steam. The Doctor finishes his rig which includes a blaster. NUCLEUS (OOV.): You're finished, Doctor. DOCTOR: Not quite. NUCLEUS (OOV.): There's no escape for you now. You are destined to become part of the purpose. DOCTOR: Well, that depends on how long it's going to take you to get out of there. NUCLEUS (OOV.): Fool. Do you think a metal barrier can contain the Swarm? It makes shrieking noises as we see a closeup of the blaster fixed to the door handle. The Doctor zips speedily into the TARDIS and slams the door, getting the end of the scarf caught. [SCENE_BREAK] Leela and K9 remain crouched behind the supervisor control desk. The scarf end disappears, then the TARDIS. Leela stands. LEELA: Doctor! The TARDIS reappears and Leela drags K9 toward it. We see the door to the hive moving. [SCENE_BREAK] Inside the TARDIS Leela and K9 come in. LEELA: Why did you not wait? The TARDIS vanishes again. At the hive door, the nucleus continues to push. We see the base from outside, and an explosion causes an eruption of flame. The flame burns for a moment, then another explosion rocks the moon. They watch the explosion on the scanner. It appears as if Titan itself is on fire - did the Doctor destroy Titan? LEELA: Is it gone? DOCTOR: Yes. LEELA: All of it? DOCTOR: Yes. Methane atmosphere. Mix well with oxygen and run. That was a good idea of mine, K9, to blow it up. K9: Affirmative. LEELA: What do you mean, it was a good idea of yours. It was my idea. DOCTOR: What was? LEELA: To blow it up. DOCTOR: Well then, you should be feeling very happy. LEELA: Yes, I am. Shall we return K9 to the Professor? The TARDIS spins in space. Is that empty black circle supposed to be Titan? [SCENE_BREAK] Back at the reception area of the Bi-Al Foundation. DOCTOR: Goodbye. MARIUS: Goodbye, Doctor, and thank you for everything you've done for us. DOCTOR: It's been a pleasure, Professor. It's been a pleasure. Do you know that without K9 I think we'd have been part of the Swarm by now. LEELA: We'd never have managed with out him. Her. It. Sorry, K9. K9: Apologies are not necessary, but thank you, mistress. MARIUS: I think K9 has taken to you. Oh. Actually, I have to return to Earth shortly and you could do me a great favour if DOCTOR: What? LEELA: Take K9 with us? MARIUS: Yes. DOCTOR: No. LEELA: Yes! Oh, please, Doctor, please, please, let's take him. MARIUS: K9 seems to have made up his own mind. The Doctor and Leela follow K9 into the TARDIS and shut the doors. MARIUS: I only hope he's TARDIS trained.
The Invisible Enemy - part 4