[Tardis]

(The Doctor uses his sonic screwdriver on Martha's mobile phone.)

DOCTOR: Right, there we go. Universal roaming. Never have to worry about a signal again.

MARTHA: No way. This is too mad. You're telling me I can phone anyone, anywhere in space and time on my mobile?

DOCTOR: As long as you know the area code. Frequent flier's privilege. Go on, try it.

(The Tardis judders.)

DOCTOR: Distress signal. Locking on. Might be a bit of

(They get knocked to the floor.)

DOCTOR: Turbulence. Sorry. Come on, Martha. Let's take a look.

[Area 30]

(Lots of steam and the place is glowing red.)

COMPUTER: Distress signal transmitted.

DOCTOR: Whoa, now that is hot.

COMPUTER: Automated distress signal transmitted.

MARTHA: Whuff, it's like a sauna in here.

DOCTOR: Venting systems. Working at full pelt, trying to cool down. Wherever it is we are. Well, if you can't stand the heat

[Area 29]

(The Doctor opens a bulkhead door and goes through. On the other side, it is labelled Area 30. Two men and a woman come running towards them.)

RILEY: (a young man) Oi, you two!

McDONNELL: (a woman) Get out of there!

RILEY: Seal that door, now!

McDONNELL: Who are you? What are you doing on my ship?

RILEY: Are you police?

DOCTOR: Why would we be police?

MARTHA: We got your distress signal.

DOCTOR: If this is a ship, why can't I hear any engines?

McDONNELL: It went dead four minutes ago.

SCANNELL: So maybe we should stop chatting and get to Engineering. Captain.

COMPUTER: Secure closure active.

McDONNELL: What?

SCANNELL: The ship's gone mad.

(Another woman comes running towards them, bulkheads slamming shut behind her.)

ERINA: : Who activated secure closure? I nearly got locked in to area twenty seven.

(The last bulkhead slams shut.)

ERINA: Who are you?

MARTHA: He's the Doctor and I'm Martha. Hello.

COMPUTER: Impact projection forty two minutes twenty seven seconds.

McDONNELL: We'll get out of this. I promise.

(Martha looks out of a porthole.)

MARTHA: Doctor.

DOCTOR: Forty two minutes until what?

MARTHA: Doctor! Look.

McDONNELL: Forty two minutes until we crash into the sun.

(The long, thin, but utilitarian spaceship is spinning towards a massive yellow fusion reactor.)

DOCTOR: How many crew members on board?

McDONNELL: Seven, including us.

SCANNELL: We transport cargo across the galaxy. Everything's automated. We just keep the ship spaceworthy.

DOCTOR: Call the others, I'll get you out.

(The Doctor runs to the door to area 30.)

RILEY: What's he doing?

McDONNELL: No, don't!

(The Doctor opens the door and is knocked down by the blast of heat. Erina puts on a welder's mask and shuts it again.)

DOCTOR: But my ship's in there!

RILEY: In the vent chamber?

DOCTOR: It's our lifeboat.

SCANNELL: It's lava.

ERINA: The temperature's going mad in there. Up three thousand degrees in ten seconds, and still rising.

RILEY: Channelling the air. The closer we get to the sun, the hotter that room's going to get.

MARTHA: We're stuck here.

DOCTOR: So, we fix the engines, we steer the ship away from the sun. Simple. Engineering down here, is it?

McDONNELL: Yes.

COMPUTER: Impact in forty twenty six.

[Engineering]

DOCTOR: Blimey, do you always leave things in such a mess?

McDONNELL: Oh, my God.

SCANNELL: What the hell happened?

(The engine is a collection of bits and pieces.)

RILEY: Oh, it's wrecked.

DOCTOR: Pretty efficiently too. Someone knew what they were doing.

McDONNELL: Where's Korwin? Has anyone heard from him or Ashton?

SCANNELL: No.

MARTHA: You mean someone did this on purpose?

(Kath McDonnell goes to the intercom.)

McDONNELL: Korwin, Ashton? Where are you? Korwin, can you answer? Where the hell is he? He should be up here.

DOCTOR: Oh, we're in the Torajii system. Lovely. You're a long way from home, Martha. Half a universe away.

MARTHA: Yeah. Feels it.

DOCTOR: And you're still using energy scoops for fusion? Hasn't that been outlawed yet?

McDONNELL: We're due to upgrade next docking. Scannell, engine report.

SCANNELL: No response.

McDONNELL: What?

SCANNELL: They're burnt out. The controls are wrecked. I can't get them back online.

DOCTOR: Oh, come on. Auxiliary engines. Every craft's got auxiliaries.

McDONNELL: We don't have access from here. The auxiliary controls are in the front of the ship.

SCANNELL: Yeah, with twenty nine password sealed doors between us and them. You'll never get there in time.

MARTHA: Can't you override the doors?

SCANNELL: No. Sealed closure means what it says. They're all dead-lock sealed.

DOCTOR: So a sonic screwdriver's no use.

SCANNELL: Nothing's any use. We've got no engines, no time, and no chance.

DOCTOR: Oh, listen to you. Defeated before you've even started. Where's your Dunkirk spirit? Who's got the door passwords?

RILEY: They're randomly generated. Reckon I know most of them. Sorry. Riley Vashti.

DOCTOR: Then what're you waiting for, Riley Vashti? Get on it.

RILEY: Well, it's a two person job. One, a technish for the questions, and the other to carry this. The oldest and cheapest security system around, eh, Captain?

McDONNELL: Reliable and simple, just like you, eh, Riley?

(Riley puts a massive backpack on. It contains a portable computer and a keyboard.)

RILEY: Try and be helpful, get abuse. Nice.

MARTHA: I'll help you. Make myself useful.

RILEY: It's remotely controlled by the computer panel. That's why it needs two.

DOCTOR: Oi. Be careful.

MARTHA: You too.

ASHTON [OC]: McDonnell. It's Ashton.

McDONNELL: Where are you? Is Korwin with you?

ASHTON [OC]: Get up to the med-centre now!

(The Doctor and McDonnell run out past Martha and Riley.)

COMPUTER: Impact in thirty four thirty one.

[Med-centre]

(A man and a woman are trying to hold a man down so they can put him in what looks like an MRI scanner, but turns out to be a stasis chamber.)

KORWIN: Argh! Stop it!

ABI: Korwin, it's Abi. Open your eyes, I need to take a look at you.

(McDonnell and the Doctor run in.)

McDONNELL: Korwin! What's happened? Is he okay?

KORWIN: Help me! It's burning me!

DOCTOR: How long's he been like this?

ABI: Ashton just brought him in.

(The Doctor scans Korwin with his screwdriver.)

McDONNELL: What are you doing?

DOCTOR: Don't get too close.

McDONNELL: Don't be so stupid. That's my husband.

ASHTON: And he's just sabotaged our ship.

McDONNELL: What?

ASHTON: He went mad. He put the ship onto secure closure, then he set the heat pulse to melt the controls.

McDONNELL: No way. He wouldn't do that.

ASHTON: I saw it happen, Captain.

DOCTOR: Korwin? Korwin, open your eyes for me a second.

KORWIN: I can't!

DOCTOR: Yeah, course you can. Go on.

KORWIN: Don't make me look at you, please.

(The Doctor takes a hypo-gun from a medical tray.)

DOCTOR: All right, all right, all right. Just relax. Sedative?

ABI: Yes.

(The Doctor sedates Korwin.)

McDONNELL: What's wrong with him?

DOCTOR: Rising body temperature, unusual energy readings. Stasis chamber. I do love a good stasis chamber. Keep him sedated in there. Regulate the body temperature. And, just for fun, run a bioscan and tissue profile on a metabolic detail.

ABI: Just doing them now.

DOCTOR: Oh, you're good. Anyone else presenting these symptoms?

ABI: Not so far.

DOCTOR: Well, that's something.

McDONNELL: Will someone tell me what is the matter with him?

DOCTOR: Some sort of infection. We'll know more after the test results. Now, allons-y, back downstairs. Hey. See about those engines. Go. Hey. Go.

(McDonnell follows Ashton out.)

DOCTOR: Call us if there's news. Any questions?

ABI: Yeah. Who are you?

DOCTOR: I'm the Doctor.

(The Doctor leaves. Korwin's hands twitch.)

COMPUTER: Heat shield failing. At twenty-five percent. Impact in thirty two fifty.

[Area 29]

(Riley is tapping away at the portable computer.)

MARTHA: Hurry up, will you?

RILEY: All right. Fix the clamp on.

MARTHA: What are you typing?

RILEY: Each door's trip code is the answer to a random question set by the crew. Nine tours back, we got drunk, thought them up. Reckoning was, if we're hijacked, we're the only ones who know all the answers.

MARTHA: So you type in the right answer

RILEY: This sends an unlock pulse to the clamp. But we only get one chance per door. Get it wrong, the whole system freezes.

MARTHA: Better not get it wrong then.

RILEY: Okay. Date of SS Pentallian's first flight. That's all right. Go!

(The lights on the clamp go green and the bulkhead door opens.)

MARTHA: Yes!

RILEY: Twenty eight more to go!

[Med-centre]

DOCTOR [OC]: Abi, how's Korwin doing? Any results from the bio-scan?

ABI: He's under heavy sedation. I'm just trying to make sense of this data. Give me a couple of minutes and I'll let you know.

(Korwin starts to wake up.)

[Engineering]

DOCTOR: Martha? Riley? How're you doing?

[Area 28]

MARTHA: Area twenty nine

[Engineering]

MARTHA [OC]: At the door to twenty eight.

DOCTOR: Yeah, you've

[Area 28]

DOCTOR [OC]: Got to move faster.

MARTHA: We're doing our best.

RILEY: Find the next number in the sequence three one three

[Engineering]

RILEY [OC]: Three three one, three six seven.

[Area 28]

RILEY: What?

MARTHA: You said the crew knew all the answers.

RILEY: The crew's changed since we set the questions.

MARTHA: You're joking.

[Engineering]

DOCTOR: Three seven nine.

MARTHA [OC]: What?

DOCTOR: It's a sequence of

[Area 28]

DOCTOR [OC]: Happy primes. Three seven nine.

MARTHA: Happy what?

[Engineering]

DOCTOR: Just enter it.

[Area 28]

RILEY: Are you sure? We only get one chance.

[Engineering]

DOCTOR: Any number that reduces to one when you take the sum of the square of its digits

[Area 28]

DOCTOR [OC]: And you continue iterating until it yields one is a happy number.

[Engineering]

DOCTOR: Any number that doesn't, isn't. A happy prime is a number that is both happy and prime. Now type it in! I don't know, talk about dumbing down! Don't they teach recreational mathematics any more?

[Area 28]

MARTHA: We're through!

DOCTOR [OC]: Keep moving, fast as you can.

[Engineering]

DOCTOR: And, Martha, be careful.

[Area 28]

DOCTOR [OC]: There may be something else on board this ship.

MARTHA: Any time you want to unnerve me, feel free.

[Engineering]

DOCTOR: Will do, thanks.

COMPUTER: Impact in thirty fifty.

[Area 27]

MARTHA: I can't believe our lives depend on some stupid pub quiz. Is that the next one?

RILEY: Oh, this is a nightmare. Classical music. Who had the most pre-download number ones, Elvis Presley or The Be-atles? How are we supposed to know that?

[Engineering]

DOCTOR: We need a backup in case they don't reach the auxiliary engines in time. Come on, think. Resources. What have we got?

MARTHA [OC]: Doctor?

DOCTOR: What is it now?

[Area 27]

MARTHA: Who had the most number ones, Elvis

[Engineering]

MARTHA [OC]: Or the Beatles. That's pre-download.

DOCTOR: Elvis.

[Area 27]

DOCTOR [OC]: No! The Beatles!

[Engineering]

DOCTOR: No! Wait! Er, er. Oh, what was that remix? Er, I don't know. I am a bit busy.

[Area 27]

MARTHA: Fine. I'll ask someone else.

[Engineering]

DOCTOR: Now, where was I? Here comes the sun. No, resources. So, the power's still working, the generator's going. If we can harness that. Ah!

McDONNELL: Use the generator to jump-start the ship.

DOCTOR: Exactly. At the very least, it'll buy us some more time.

McDONNELL: That is brilliant.

DOCTOR: I know. See? Tiny glimmer of hope.

SCANNELL: If it works.

McDONNELL: Oh, believe me. You're going to make it work.

DOCTOR: That told him.

COMPUTER: Impact in twenty nine forty six.

[Francine's home]

(Martha phones her mum on her mobile.)

FRANCINE: Hello?

MARTHA [OC]: Mum? It's me.

[Area 27]

MARTHA: It's Martha. Wow!

FRANCINE [OC]: Where are you?

[Francine's home]

FRANCINE: Don't you check your messages? I've been calling you.

[Area 27]

MARTHA: Actually, a bit busy. Need you to do something

[Francine's home]

MARTHA [OC]: For me.

FRANCINE: No, listen to me.

[Francine's home]

FRANCINE: We have to talk

[Area 27]

FRANCINE [OC]: About this Doctor.

MARTHA: Mum, please, not now. I need you to look something up on the internet.

[Francine's home]

FRANCINE: Do it yourself. You've got a computer.

[Area 27]

MARTHA: Oh, just do it, will you? Please.

[Francine's home]

FRANCINE: When did you get so rude? I'll tell you when. Ever since you met that man.

MARTHA: I need to know who had more number ones.

[Area 27]

MARTHA: The Beatles or Elvis?

[Francine's home]

FRANCINE: Hang on, the mouse is unplugged. Okay, I'm on.

[Area 27]

FRANCINE [OC]: What is this, a pub quiz?

MARTHA: Yeah, a pub quiz.

[Francine's home]

FRANCINE: Using your mobile is cheating.

[Area 27]

MARTHA: Have you found it?

FRANCINE [OC]: There's over four hundred thousand results. Give me a minute.

COMPUTER: Impact in twenty eight fifty.

[Med-centre]

ABI: Doctor, these readings are starting to scare me.

[Engineering]

DOCTOR: What do you mean?

ABI [OC]: Well, Korwin's body's changing. His whole biological make-up.

[Med-centre]

ABI: It's impossible.

(Abi hears a noise behind her, and sees Korwin's reflection in a steel bowl above the intercom. He is standing there, eyes shut.)

ABI: This is Med-centre. Urgent assistance requested.

[Engineering]

ABI [OC]: Urgent assistance!

DOCTOR: Stay here! Keep working!

(The Doctor runs out, and McDonnell follows him.)

[Med-centre]

ABI: Urgent assistance!

[Engineering]

ERINA: Abi, they're on their way.

[Med-centre]

ABI: What's happening to you?

(Korwin's voice is not his own.)

KORWIN: Burn with me.

[Area 27]

KORWIN [OC]: Burn with me.

[Corridor]

(Scannell has followed the Doctor and McDonnell.)

SCANNELL: Captain?

DOCTOR: I told you to stay in Engineering.

SCANNELL: I only take orders form one person round here.

DOCTOR: Oh, is he always this cheery?

[Francine's home]

FRANCINE: Elvis.

[Area 27]

MARTHA: What? Really. Elvis.

[Med-centre]

KORWIN: Burn with me.

ABI: Korwin, you're sick.

KORWIN: Burn with me!

(Korwin opens his eyelids, to reveal a blinding white light.)

[Area 27]

(Martha and Riley are through.)

MARTHA: Mum, you're a star!

[Francine's home]

FRANCINE: Now, we need to have a serious

(Abi's scream comes over the intercom, and Martha's phone.)

FRANCINE: What was that?

[Area 26]

MARTHA: I've got to go.

(Martha finishes the call. Korwin puts on heavy-duty protective gauntlets and a helmet, and lowers the Polaroid filter.)

MARTHA: Doctor, what were those screams?

[Corridor]

DOCTOR: Concentrate on those doors. You've got to keep moving

[Area 26]

DOCTOR [OC]: Forward.

COMPUTER: Impact in twenty seven oh six.

[Med-centre]

(The Doctor, McDonnell and Scannell run in.)

McDONNELL: Korwin's gone.

SCANNELL: Oh, my God.

(The image of a figure is burnt onto the metal x-ray shield.)

SCANNELL: Tell me that's not Lerner.

DOCTOR: Endothermic vaporisation. I've never seen one this ferocious. Burn with me.

SCANNELL: That's what we heard Korwin say.

McDONNELL: What? Do you think? No way. Scannell, tell him. Korwin is not a killer. He can't vaporise people. He's human!

DOCTOR: His bioscan results. Internal temperature, one hundred degrees! Body oxygen replaced by hydrogen. Your husband hasn't been infected, he's been overwhelmed.

McDONNELL: The test results are wrong.

DOCTOR: But what is it, though? A parasite? A mutagenic virus? Something that needs a host body, but how did it get inside him?

McDONNELL: Stop talking like he's some kind of experiment.

DOCTOR: Where's the ship been? Have you made planet-fall recently? Docked with any other vessels? Any kind of external contact at all?

McDONNELL: What is this, an interrogation?

DOCTOR: We've got to stop him before he kills again.

McDONNELL: We're just a cargo ship.

SCANNELL: Doctor, if you give her a minute.

McDONNELL: I'm fine. I need to warn the crew. Everybody, listen to me. Something has infected Korwin. We think he killed Abi Lerner. None of you must go anywhere near him, is that clear?

[Engineering]

ASHTON: Understood, Captain. Erina? Get back here with that equipment.

[Storage area]

(Erina mutes the intercom.)

ERINA: Whatever you say, boss. Go there. Come back. Fetch this. Carry these. Make drinks. Sweep up. Please, kill me now.

(She closes the locker door and Korwin is standing there.)

KORWIN: Burn with me. Burn with me.

(Korwin lifts the filter and the white light streams out. Erina screams.)

COMPUTER: Impact in twenty four fifty one.

[Med-centre]

McDONNELL: Is the infection permanent? Can you cure him?

DOCTOR: I don't know.

McDONNELL: Don't lie to me, Doctor. Eleven years we've been married. We chose this ship together. He keeps me honest, so I don't want false hope.

DOCTOR: The parasite's too aggressive. Your husband's gone. There's no way back. I'm sorry.

McDONNELL: Thank you.

DOCTOR: Are you certain nothing happened to provoke this? Nobody's working on anything secret? Because it's vital that you tell me.

McDONNELL: I know every inch of this ship. I know every detail of my crew's lives. There is nothing.

DOCTOR: Then why is this thing so interested in you?

McDONNELL: I wish I knew.

(Riley and Martha have made it through bulkhead 17.)

[Engineering]

MARTHA [OC]: Doctor, we're through to area seventeen.

DOCTOR [OC]: Keep going.

[Area 16]

DOCTOR [OC]: You've got to get to area one and reboot those engines.

[Engineering]

(Ashton is working underneath the engine when someone enters.)

ASHTON: You got those tools, Erina? Because I

(Ashton is pulled out from underneath the engine by his ankles.)

ASHTON: Whoa!

(Korwin pulls Ashton to his feet by his gauntleted hands.)

ASHTON: Korwin, it's me. We're mates.

KORWIN: They are getting too far. We must share the light.

(Korwin holds Ashton's head. It burns. He screams.)

COMPUTER: Heat shields failing. At twenty percent.

[Area 17]

RILEY: Come on!

(Riley hits his portable computer.)

RILEY: Everything on this ship is so cheap.

(The bulkhead to area 18 behind them clangs open.)

RILEY: Who's there?

(A figure appears through the smoke.)

MARTHA: Is that Korwin?

RILEY: No, wait a minute.

(The figure is wearing a helmet.)

RILEY: Oh, Ashton, what're you doing?

ASHTON: Burn with me.

RILEY: Well, if you want to help

ASHTON: Burn with me. Burn with me.

(Ashton moves to raise the Polaroid filter.)

MARTHA: Move! Come on!

[Escape pod]

(She opens the door to a small adjacent area, then shuts it when they are both in. Ashton appears at the window in the door, so Riley opens a small hatch and they climb through. Ashton touches some controls and a second door slides closed over the hatch.)

RILEY: What is happening on this ship?

MARTHA: Never mind that, where are we?

COMPUTER: Airlock sealed. Jettison escape pod.

MARTHA: That doesn't mean us? Doctor!

COMPUTER: Pod jettison initiated.

MARTHA: Doctor! We're stuck in an escape pod off the area seventeen airlock.

[Engineering]

MARTHA [OC]: One of the crew's trying to jettison us! You've got to help us!

[Escape pod]

MARTHA: Tell me you can stop it.

[Storage area]

McDONNELL: Why is this happening?

DOCTOR: Stay here. I mean it this time! Jump start those engines!

(McDonnell and Scannell see a charred shape on the wall.)

McDONNELL: It's picking us off, one by one.

[Escape pod]

COMPUTER: Jettison held.

RILEY: Thank you.

(Ashton uses the keypad outside.)

COMPUTER: Jettison reactivated.

(Martha screams.)

RILEY: Come on.

(Riley and Ashton are fighting via keypads as the Doctor runs to help them.)

RILEY: Tsilpinski sequence. This'll get him.

COMPUTER: Jettison held. Escape pod stabilised.

MARTHA: You're pretty good.

(Ashton types something else into his keypad.)

[Engineering]

McDONNELL: Ashton!

SCANNELL: Someone's hacked into the systems. I can't reroute the generators. There's no way I'm going to be able to jump-start this ship! Who the hell did that!

(Scannell walks away. A figure walks towards McDonnell.)

McDONNELL: Korwin? What are you? Why are you killing my crew? What did you do to him? What have you done to my husband?

(Korwin stops.)

McDONNELL: You recognise me. Korwin, you know me. It's Kath. Your wife.

KORWIN: My wife.

McDONNELL: That's right. You're still in there. I'm your wife.

KORWIN: It's your fault.

[Area 17]

(The battle of the keypads has started again.)

DOCTOR: That's enough! What do you want? Why this ship? Tell me.

(Ashton puts his fist through the keypad.)

[Escape pod]

COMPUTER: Jettison activated.

RILEY: He's smashed the circuit. I can't stop it. I can't stop it!

[Engineering]

(McDonnell has backed up to where Scannell is standing.)

McDONNELL: What do you mean, it's my fault?

KORWIN: It's your fault. Now burn with me!

(Korwin is about to raise the visor when dry ice engulfs him from above. Scannell is turning a valve wheel rapidly.)

McDONNELL: What are you doing?

SCANNELL: Freezing him. Ice vents.

McDONNELL: You'll kill him!

[Area 17]

DOCTOR: Come on. Let's see you. I want to know what you really are.

(Ashton stands nose to nose with the Doctor and raises his hand to the visor. Korwin collapses in Engineering and Ashton doubles over in pain.)

COMPUTER: Airlock sealed.

(Ashton walks past the Doctor, back down the ship. The Doctor uses the intercom.)

DOCTOR: McDonnell? Ashton's heading in your direction.

[Engineering]

DOCTOR [OC] He's been infected, just like Korwin!

SCANNELL: Korwin's dead, Doctor.

[Escape pod]

MARTHA: This thing's locked!

COMPUTER: Airlock decompression completed. Jettisoning pod.

(The Doctor looks through the window in the airlock door.)

MARTHA: Doctor!

DOCTOR: I'll save you!

RILEY: Martha, it's too late.

MARTHA: Doctor!

DOCTOR: I'll save you!

MARTHA: I can't hear you!

DOCTOR [silent]: I'll save you!

(The pod leaves the side of the ship and floats towards the sun.)

MARTHA: I'm sorry.

[Engineering]

COMPUTER: Impact in seventeen oh five.

(McDonnell kneels by the body of her husband.)

SCANNELL: What did he mean, your fault? What are you doing? Don't touch him. He's infected. We don't know how it spreads.

McDONNELL: You murdered him!

SCANNELL: He was about to kill you.

McDONNELL: He recognised me.

SCANNELL: You heard the Doctor. It… it isn't Korwin anymore.

McDONNELL: The Doctor doesn't know. None of us knows!

SCANNELL: So what are you going to do, sit there until we burn? Because without you none of us stand a chance of getting out of here.

DOCTOR [OC]: Scannell! I need a spacesuit in area seventeen now!

SCANNELL: What for?

[Area 17]

DOCTOR: Just get down here!

[Engineering]

McDONNELL: Well, go on. Do what he says.

SCANNELL: Ashton's still out there.

McDONNELL: I'll deal with him.

[Escape pod]

RILEY: The wonderful world of space travel. The prettier it looks, the more likely it is to kill you.

MARTHA: He'll come for us.

RILEY: No, it's too late. Our heat shields will pack in any minute, and then we go into free fall. We'll fall into the sun way before he has a chance to do anything.

MARTHA: You don't know the Doctor. I believe in him.

RILEY: Then you're lucky. I've never found anyone worth believing in.

MARTHA: No girlfriend? Boyfriend?

RILEY: The job doesn't lend itself to stable relationships.

MARTHA: Family, then?

RILEY: My dad's dead, and I haven't seen my mum in six years. She didn't want me to sign up for cargo tours. Things were said, and since then, all silent. She wanted to hold on to me, I know that. Oh, she's so stubborn.

MARTHA: Yeah, well, that's families.

RILEY: What about you?

MARTHA: Full works. Mum, Dad, Dad's girlfriend, brother, sister. No silence there. So much noise. Oh, God! They'll never know! I, I'll just have disappeared, and they'll always be waiting.

RILEY: Call them.

[Corridor]

(Ashton arrives at the bottom of the metal staircase up to Med-centre.)

McDONNELL [OC]: Ashton.

(McDonnell is at the top of the stairs. Ashton follows her. Once in the Med-centre, McDonnell punches Ashton in the stomach then pushes him head-first into the stasis chamber. She manages to switch it on and the temperature around Ashton's head drops rapidly until it kills him.)

[Area 17]

(The Doctor is now in a spacesuit.)

SCANNELL: I can't let you do this.

DOCTOR: You're wasting your breath, Scannell. You're not going to stop me.

SCANNELL: You want to open an airlock in flight on a ship spinning into the sun. No one can survive that.

DOCTOR: Oh, just you watch.

SCANNELL: You open that airlock, it's suicide. This close to the sun, the shields will barely protect you.

DOCTOR: If I can boost the magnetic lock on the ship's exterior, it should remagnetise the pod. Now, while I'm out there, you have got to get the rest of those doors open. We need those auxiliary engines.

SCANNELL: Doctor, will you listen! They're too far away. It's too late.

DOCTOR: I'm not going to lose her.

(The Doctor puts on the helmet and goes into the airlock.)

COMPUTER: Decompression initiated. Impact in twelve fifty five.

[Francine's home]

(Her mobile phone rings.)

FRANCINE: Hello.

MARTHA [OC]: It's me again.

[Escape pod]

MARTHA: Sorry about earlier.

FRANCINE [OC]: Is everything all right?

MARTHA: Yeah. Of course.

[Francine's home]

FRANCINE: Martha?

[Escape pod]

MARTHA: Mum, I. you know I love you, don't you?

[Francine's home]

FRANCINE: Of course I do. What's bought this on?

[Escape pod]

MARTHA: I never say it. I never get the time. I never think of it, and then

[Francine's home]

MARTHA [OC]: I really love you. Tell Dad, Leo and Tish that I love them.

(A blonde woman in a black suit is monitoring the conversation.)

FRANCINE: Martha, what's wrong?

MARTHA [OC]: Nothing. I promise.

FRANCINE: Where are you?

MARTHA [OC]: Just out.

FRANCINE: With anyone nice?

[Escape pod]

MARTHA: Some mates.

FRANCINE [OC]: What mates?

MARTHA: Mum, can we not just talk?

[Francine's home]

FRANCINE: Of course. What do you want to talk about?

[Escape pod]

MARTHA: I don't know. Anything! What you had for breakfast. What you watched on telly last night. How much you're going to kill Dad next time you see him. Just anything.

[Francine's home]

FRANCINE: Is the Doctor with you? Is he there, now?

[Escape pod]

MARTHA: Mum, just leave it.

FRANCINE [OC]: It's a simple enough question.

MARTHA: I'd better go.

[Francine's home]

(The woman makes the circular keep going gesture.)

FRANCINE: Er, no, Martha, wait.

[Escape pod]

MARTHA: See you, Mum.

(Martha ends the call, then she and Riley hug each other, crying.)

[Airlock]

COMPUTER: Impact in eleven fifteen. Heat shield failing. At ten percent.

(The Doctor opens the outer airlock door and the unfiltered sunlight streams in. Gritting his teeth, he climbs outside and reaches for a row of four buttons on the ship's hull. He has to hold on to the edge of the airlock because there is no safety line.)

DOCTOR: Come on! Go on, my son!

(He presses two buttons then stretches for the box just beyond them.)

SCANNELL [OC]: Doctor, how're you doing?

DOCTOR: I can't, I can't reach! I don't know how much longer I can last.

SCANNELL: Come on. Don't give up now.

(He rips off the cover of the box, and with a big shout pulls the lever down.)

[Escape pod]

(There is a big jolt. The computer screen says remagnetising.)

RILEY: We're being pulled back!

MARTHA: I told you! It's the Doctor!

(The Doctor gets back into the airlock as the escape pod returns to its dock. He looks at the sun.)

DOCTOR: It's alive. It's alive. It's alive!

[Area 10]

SCANNELL: Doctor, close the airlock now! That pod's going to smash into him.

McDONNELL: Stay here.

(McDonnell gives Scannell the clamp and runs back.)

COMPUTER: Impact in eight fifty seven.

[Area 17]

COMPUTER: Airlock recompression completed.

(The Doctor has his eyes closed tight as he takes off his helmet and crawls out of the airlock. The pod docks.)

MARTHA: Doctor! Doctor! Are you okay?

(The Doctor opens his eyes briefly. A white light shines from them.)

DOCTOR: Stay away from me!

McDONNELL: What's happened?

DOCTOR: It's your fault, Captain McDonnell!

McDONNELL: Riley, get down to area ten and help Scannell with the doors. Go!

(Riley runs off.)

DOCTOR: You mined that sun. Stripped its surface for cheap fuel. You should have scanned for life!

McDONNELL: I don't understand.

MARTHA: Doctor, what are you talking about?

DOCTOR: That sun is alive. A living organism. They scooped out its heart, used it for fuel, and now it's screaming!

McDONNELL: What do you mean? How can a sun be alive? Why is he saying that?

DOCTOR: Because it's living in me.

McDONNELL: Oh, my God.

DOCTOR: Humans! You grab whatever's nearest and bleed it dry! You should have scanned!

McDONNELL: It takes too long. We'd be caught. Fusion scoops are illegal.

DOCTOR: You've got to freeze me, quickly.

MARTHA: What?

DOCTOR: Stasis chamber. You've got to take it below minus two hundred. Freeze it out of me! It'll use me to kill you if you don't. The closer we get to the sun, the stronger it gets! Med-centre, quickly! Quickly!

MARTHA: Help me!

COMPUTER: Impact in seven thirty.

(In Engineering, Korwin starts to thaw. His hand moves and picks up the helmet.)

[Area 10]

SCANNELL: What's your favourite colour?

RILEY: You what?

SCANNELL: It's the question.

RILEY: Purple! Or did I say orange?

SCANNELL: Come on!

[Med-centre]

(Martha grabs the instruction manual.)

MARTHA: I can do it!

DOCTOR: Martha, where are you?

MARTHA: It's all right, I'm here. Just help me get him up. Stasis chamber, minus two hundred, yeah?

McDONNELL: No, you don't know how this equipment works. You'll kill him. Nobody can survive those temperatures.

MARTHA: He's not human. If he says he can survive, then he can.

McDONNELL: Let me help you, then.

MARTHA: You've done enough damage.

(The Doctor lies in the stasis chamber.)

DOCTOR: Ten seconds. That's all I'll be able to take. No more. Martha!

MARTHA: Yeah?

DOCTOR: It's burning me up. I can't control it. If you don't get rid of it, I could kill you. I could kill you all. I'm scared! I'm so scared!

MARTHA: Just stay calm. You saved me, now I return the favour. Just believe in me.

DOCTOR: It's burning through me. Then what'll happen?

MARTHA: That's enough! I've got you.

DOCTOR: There's this process, this thing that happens if I'm about to die.

MARTHA: Shush. Quiet now. Because that is not going to happen. Are you ready?

DOCTOR: No.

(Martha uses the joystick to roll the Doctor completely into the chamber, then types 200 into the keypad and presses the green button. The Doctor screams as his body temperature falls.)

COMPUTER: Heat shields failing. At five percent. (In Engineering, Korwin stands up just as a computer monitor reports - power drain medcentre stasis chamber active. He goes to a lever, pulls it up, and the monitor changes to stasis chamber inactive. The power is cut at minus 70 degrees. The Doctor is covered in frost.)

DOCTOR: No! Martha, you can't stop it. Not yet.

MARTHA: What happened?

McDONNELL: Power's been cut in Engineering.

MARTHA: But who's down there?

McDONNELL: Leave it to me.

(McDonnell leaves.)

COMPUTER: Impact in four forty seven.

[Area 4]

SCANNELL: Are we going to do it in time?

[Med-centre]

MARTHA: Come on. You're defrosting.

(The ice has gone from the Doctor's body.)

DOCTOR: Martha, listen! I've only got a moment. You've got to go!

MARTHA: No way.

DOCTOR: Get to the front. Vent the engines. Sun particles in the fuel, get rid of them.

MARTHA: I am not leaving you.

DOCTOR: You've got to give back what they took.

MARTHA: Doctor!

DOCTOR: Please go!

MARTHA: I'll be back for you.

COMPUTER: Impact in four oh eight.

[Engineering]

(Korwin blocks McDonnell's way.)

McDONNELL: You were right. It was my fault.

(McDonnell reaches for the lever. Korwin steps forward then starts to raise his Polaroid filter. She runs back and he follows.)

COMPUTER: Impact in three forty three.

[Airlock]

(Martha runs through area 21 as Korwin catches up with McDonnell, hiding in an airlock. This one has no escape pod.)

McDONNELL: I didn't know. I really didn't know. Korwin, please stop.

KORWIN: Everyone must burn!

(McDonnell closes the outer airlock door then activates the intercom.)

McDONNELL: Riley, Scannell.

[Area 4]

McDONNELL [OC]: I'm sorry.

SCANNELL: McDonnell. McDonnell!

[Airlock]

(McDonnell opens the outer airlock door and puts her arms around Korwin's neck.)

McDONNELL: I love you.

(They fall towards the sun together.)

[Area 4]

COMPUTER: Exterior airlock open.

RILEY: It's the last door. We've got to keep going.

COMPUTER: Impact in two seventeen. Primary engines critical.

(The Doctor falls out of the stasis chamber and crawls across the floor.)

COMPUTER: Repeat. Primary engines critical. Survival estimate projection zero percent.

[Area 22]

DOCTOR: Martha!

MARTHA [OC]: Doctor! What are you doing?

DOCTOR: I can't fight it. Give it back or burn with me.

[Area 4]

DOCTOR [OC]: Burn with me, Martha.

COMPUTER: Impact in one twenty one.

[Area 1]

RILEY: Got it!

COMPUTER: Life support systems reaching critical. Repeat. Life support systems reaching critical. Impact in one oh six.

(Scannell and Riley quickly enter commands into various computers.)

COMPUTER: Collision alert. Collision alert.

RILEY: It's not working. Why's it not working?

COMPUTER: Collision alert. Fifty eight seconds to fatal impact.

MARTHA: Vent the engines. Dump the fuel.

SCANNELL: What?

MARTHA: Sun particles in the fuel. Get rid of them. Do it. Now!

(They obey.)

MARTHA: Come on, Doctor. Hold on.

(Bang!)

COMPUTER: Fuel dump in progress. Fuel dump in progress.

(The light goes out in the Doctor's eyes, and he keels over.)

SCANNELL: There! The auxiliaries are firing!

(The ship lurches, then starts to pull away from the sun as the countdown reaches one second.)

COMPUTER: Impact averted. Impact averted. Impact averted.

RILEY: We're clear. We've got just enough reserves.

MARTHA: Doctor!

(She runs back down the body of the ship to embrace the Doctor.)

[Area 30]

(Later, in the safety of interstellar space.)

SCANNELL: This is never your ship.

DOCTOR: Compact, eh? And another good word, robust. Barely a scorch mark on her.

MARTHA: We can't just leave you drifting with no fuel.

RILEY: We've sent out an official mayday. The authorities'll pick us up soon enough.

SCANNELL: Though how we explain what happened

DOCTOR: Just tell them. That sun needs care and protection just like any other living thing.

(The Doctor goes into the Tardis.)

RILEY: So, er, you're off then. No chance I'll see you again?

MARTHA: Not really. It was nice, not dying with you. I reckon you'll find someone worth believing in.

RILEY: I think I already did.

(Martha kisses Riley.)

MARTHA: Well done. Very hot.

(She goes into the Tardis.)

[Tardis]

MARTHA: So. Didn't really need you in the end, did we? Sorry. How are you doing?

DOCTOR: Now, what do you say? Ice skating on the mineral lakes of Kur-ha. Fancy it?

MARTHA: Whatever you like.

DOCTOR: By the way, you'll be needing this.

(A Tardis key on a chain.)

MARTHA: Really?

DOCTOR: Frequent flier's privilege. Thank you.

MARTHA: Oh, no. Mum.

[Francine's home]

(Francine answers her mobile phone.)

FRANCINE: Hello?

[Tardis]

MARTHA: It's me again.

FRANCINE: Three calls in one day.

MARTHA: I'm sorry about earlier. Over emotional. Mad day.

FRANCINE [OC]: What are you doing tonight?

[Francine's home]

FRANCINE: Why don't you come round? I'll make something nice and we can catch up.

[Tardis]

MARTHA: Yeah. Tonight. Do my best. Er, just remind me. What day is it again?

FRANCINE [OC]: Election day.

MARTHA: Right. Of course. I'll be round for tea. Roughly.

[Francine's home]

FRANCINE: And what about

MARTHA [OC]: Anyway, I've got to go!

[Tardis]

MARTHA: See you later. Love you.

[Francine's home]

(The blonde woman takes out her ear buds and holds out an evidence bag. Francine drops her mobile phone into it. Two men in black stand silently by.)

FRANCINE: That's all?

DEXTER: For now. Have you voted?

FRANCINE: Of course. Just don't expect me to tell you who for.

DEXTER: Thanks for all you're doing, Mrs Jones. Mister Saxon will be very grateful.