4x05 - The Poison Sky

Recap of Episode 4, ending with the scene when Wilf is choking in the car and the Doctor and Donna are trying to free him.

***
OPENING CREDITS

DAVID TENNANT
CATHERINE TATE
and
FREEMA AGYEMAN

THE POISON SKY
by Helen Raynor
***

DONNA
He's gonna choke! Doctor!

DOCTOR
It won't open!

Sylvia rushes to the car with an axe and smashes the windscreen.

SYLVIA
Well, don't just stand there! Get him out!

***
UNIT OFFICER
All soldiers to a door! Make the factory secure and take positions on the ground floor!

COLONEL MACE
Wicowsky, take the soldiers into the factory! Make the area secure. Seal off doors and windows.

Soldiers are pushing the cars out of the factory.

SOLDIER
We've tried everything, it just won't stop!

Colonel Mace goes into the UNIT field base.

COLONEL MACE
What have we got?

CAPTAIN PRICE
ATMOS is running wild, sir. It can't be stopped, it's everywhere. The whole planet.

The Martha clone enters the UNIT base and uses Martha's level 1 security clearance to get into the NATO defence system.

***
WILF
Thanks!

DONNA
I can't believe you've got an axe!

SYLVIA
Burglars!

DOCTOR
Get inside the house. Just try and close off the doors and windows.

Ross pulls up in a black cab.

ROSS
Doctor! This is all I could find that hasn't got ATMOS.

The Doctor runs to the cab, shouting back to Donna who is still with Wilf and Sylvia.

DOCTOR
Donna, you coming?

DONNA
Yeah!

SYLVIA
Donna! Don't go! Look what happens every time that Doctor appears! Stay with us, please.

WILF
You go my darling!

SYLVIA
Dad!

WILF
Don't listen to her! You go with the Doctor! That's my girl!...

Donna gets into the cab, though feeling guilty to leave her family.

WILF
Bye!

***
The Martha clone downloads the security protocols to her PDA.

COMMANDER SKORR
Success, the operative has the necessary information.

GENERAL STAAL
Good work for a female. Now she must be protected.

COMMANDER SKORR
I will prepare an attack squad.

He leaves.

LUKE
This is it, isn't it! Oh man, this is war!

GENERAL STAAL
How does it feel, boy?

LUKE
Magnificent!

***
NEWS 24 NEWSREADER
The Government has declared a state of emergency. People are being told to stay away from all cars with ATMOS devices attached.

AMNN NEWSREADER
The gas appears to be toxic. We are warning anyone and everyone, stay away from the cars. Repeat, stay away from your cars.

***
The taxi pulls up to the ATMOS factory, the Doctor and Donna exit.

DOCTOR
Ross, look after yourself, get inside the building.

ROSS
Will do. (over radio) Greyhound 40 to Trap 1, I have just returned the Doctor to base safe and sound, over.

The Martha clone is hears Ross and hurries to Colonel Mace.

COLONEL MACE (over radio)
Trap 1, received. Over.

MARTHA CLONE
Sir, message from the Doctor, he says Code Red Sontaran.

COLONEL MACE (over radio)
All troops, Code Red Sontaran. Code Red Sontaran.

***
DONNA
The air is disgusting!

DOCTOR
It's not so bad for me, go on, get inside the TARDIS. Oh, never given you a key! (he pulls out a key) Keep that! Go on, that's yours! Quite a big moment really!

DONNA
Yeah, maybe we can get sentimental after the world's finished choking to death!

DOCTOR
Good idea!

DONNA
Where are you going?

DOCTOR
Stop a war!

He rushes to the UNIT field base while Donna runs to the TARDIS.

***
DOCTOR
Right then, here I am, good. Whatever you do, Colonel Mace, do not engage the Sontarans in battle, there is nothing they like better than a war. Just leave this to me.

COLONEL MACE
And what are you going to do?

DOCTOR
I’ve got the TARDIS, I’m gonna get on board their ship.

The Martha clone presses a button on the PDA, the hypnotised privates activate.

DOCTOR (to the Martha clone)
Come on!

***
The privates place devices on the TARDIS.

PRIVATE HARRIS
Ready for transport.

The TARDIS is teleported to the Sontaran ship, with Donna inside.

GENERAL STAAL
The spoils of war! The Doctor’s infamous vessel in Sontaran hands.

LUKE
It’s time I made a move, sir, I have soldiers of my own. I’ll tell them of the honour and the glory, sir! I’ll tell them that Planetfall is coming!

He teleports back to Earth.

COMMANDER SKORR
He is behaving exactly as predicted, sir.

Donna peeks out of the TARDIS door, then quickly closes it as she glimpses the Sontarans.

GENERAL STAAL
None of the humans can guess our true purpose.

***
The Doctor runs down the alleyway to find the TARDIS gone.

MARTHA CLONE
But... where’s the TARDIS?

DOCTOR
Taste that, in the air. Yecch. That sort of metal tang. Teleport exchange. It’s the Sontarans, they’ve taken it. I’m stuck, on Earth like... like an ordinary person. Like a human! How rubbish is that! Sorry, no offence, but come on!

MARTHA CLONE
So what do we do?

DOCTOR
Well... I mean it’s shielded, they could never detect it.

He stares at her.

MARTHA CLONE
What?

DOCTOR
I’m just wondering, have you phoned your family and Tom?

MARTHA CLONE
No, what for?

DOCTOR
The gas. Tell them to stay inside.

MARTHA CLONE
Course I will, yeah, but, what about Donna? I mean, where’s she?

DOCTOR
Oh, she’s gone home. She’s not like you, she’s not a soldier. Right. So, avanti!

***
Rattigan’s students look out over London.

LUKE
Leave it. Turn away. Civilisation is falling!

MALE STUDENT
But it’s all over the news, sir, it’s everywhere. Paris and New York.

LUKE
It’s time I told you, all of you. It’s time I revealed what our work has been for!

***
The Doctor and the Martha clone enter the UNIT base.

DOCTOR
Change of plan!

COLONEL MACE
Good to have you fighting alongside us, Doctor.

DOCTOR
I’m not fighting, I’m not-fighting, as in not hyphen fighting, got it? Now, does anyone know what this gas is yet?

MARTHA CLONE
We’re working on it.

CAPTAIN PRICE
It’s harmful, but not lethal until it reaches 80% density. We’re having the first reports of deaths from the centre of Tokyo City.

DOCTOR
And who are you?

CAPTAIN PRICE (salutes)
Captain Marion Price, sir.

DOCTOR
Oh, put your hand down. Don’t salute.

COLONEL MACE
Jodrell Bank’s traced a signal, Doctor, coming from 5000 miles above the Earth. We’re guessing that’s what triggered the cars.

DOCTOR
The Sontaran ship.

COLONEL MACE
NATO has gone to Defcon One, we’re preparing a strike.

DOCTOR
You can’t do that, nuclear missiles won’t even scratch the surface. Let me talk to the Sontarans.

COLONEL MACE
You’re not authorised to speak on behalf of the Earth.

DOCTOR
I’ve got that authority, I earned that a long time ago. (he uses the sonic screwdriver to connect the UNIT systems to the Sontaran ship) Calling the Sontaran Command Ship under Jurisdiction Two of the Intergalactic Rules of Engagement. This is The Doctor.

***
The transmission is also received inside the TARDIS. For a split second, Rose Tyler appears on a screen, but fades away before Donna gets there, so she only sees the Doctor calling from the UNIT base.

DONNA
Doctor, I’m here, can you hear me?

***
GENERAL STAAL
Doctor, breathing your last?

COLONEL MACE
My God, they’re like trolls.

DOCTOR (to the Colonel)
Yeah, loving the diplomacy, thanks. (louder, to the Sontarans) So, tell me, General Staal, since when did you lot become cowards?

GENERAL STAAL
How dare you!

COLONEL MACE
Oh, that’s diplomacy?

GENERAL STAAL
Doctor, you impugn my honour!

DOCTOR
Yeah, I’m really glad you didn’t say belittle cos then I’d have a field day. But poison gas? That’s the weapon of a coward and you know it. Staal, you could blast this planet out of the sky, and yet you’re sitting up above watching it die. Where’s the fight in that? Where’s the honour? Or, are you lot planning something else? Cos this isn’t normal Sontaran warfare. What are you lot up to?

GENERAL STAAL
A general would be unwise to reveal his strategy to the opposing forces.

DOCTOR
Aaah, the war’s not going so well, then? Losing, are we?

GENERAL STAAL
Such a suggestion is impossible.

COLONEL MACE
What war?

DOCTOR
The war between the Sontarans and the Rutans. It’s been raging, far out in the stars for 50,000 years. 50,000 years of bloodshed, and for what?

GENERAL STAAL
For victory. Sontar-ha!

SONTARANS
Sontar-ha! Sontar-ha! Sontar-ha!

DOCTOR (rolling the eyes)
Give me a break.

He pulls out the sonic screwdriver and changes the channel to the cartoon, Tommy Zoom.

COLONEL MACE
Doctor. I would seriously recommend that this dialogue is handled by official Earth representation.

The Doctor sonics the channel back to the Sontaran ship.

DOCTOR
Finished?

GENERAL STAAL
You will not be so quick to ridicule when you’ll see our prize. Behold! (he gestures to the TARDIS behind him) We are the first Sontarans in history to capture a TARDIS.

DOCTOR
Well. As prizes go, that’s... noble. (Donna is watching the Doctor on a screen) As they say in Latin, Donna nobis pacem.

DONNA
That’s me. I’m here!

DOCTOR
Did you never wonder about its design? It's phone box. It contains a phone. A telephonic device for communication. Sort of symbolic. Like if only we could communicate. You and I.

GENERAL STAAL
All you have communicated is your distress, Doctor.

DONNA
Oh my god.

She picks up Martha’s mobile and opens it.

DOCTOR
Big mistake though. Showing it to me.

DONNA
But who do I phone?

DOCTOR (lifting up a device)
Cos I’ve got remote control.

GENERAL STAAL
Cease transmission!

DONNA
Doctor, what number are you on?

The screen goes black.

DONNA
You haven’t even got a number!

GENERAL STAAL
Remove the box from the War Room, beyond the transmission field.

DOCTOR
Oh, well.

He gets up.

COLONEL MACE
That's achieved nothing.

DOCTOR
Oh, you’d be surprised.

Donna is thrown around the TARDIS as a group of Sontarans push the TARDIS away.

DONNA
But what do I do?

***
LUKE
All this stuff we’ve been building. All this invention. Where’s it been heading? Gravity intensifiers, hydroponics, atmospheric conversion, ecoshell. More then enough to build a brand new world!

MALE STUDENT
Luke, we haven’t got time for this. I’ve got to find my parents.

LUKE
Oh, but this isn’t just theory. I’m talking Planetfall. For all of us. A brand new start for a brand new human race. Look. (he opens a 3-D projection of a planet) A new world. Far out. Beyond Alpha Geminorium, just waiting for us. Its official destination is Castor 36. I think of it as Earth Point Two. I did wonder about Rattigan’s World, but... we can take a vote on that.

MALE STUDENT
What the hell are you on about?

LUKE
This is where we’re going. I have partners willing to take us there.

FEMALE STUDENT
Oh, he’s lost it. I haven’t got time for this.

LUKE (turning the projector off)
Excuse me, I haven’t finished. Where are you going?

FEMALE STUDENT
To find my brother.

LUKE
I didn’t say you could leave.

FEMALE STUDENT
I told him to put ATMOS is his car. I’ve got to go and help him.

LUKE (pulling out a gun)
Stay where you are!

FEMALE STUDENT
What do you think your doing?

MALE STUDENT
Luke. Put that down.

LUKE
But... I did this for you. Don’t you see? We’ve spent all our lives excluded. The clever ones. They... They’ve laughed at us. And pulled us down. Those ordinary people out there. Those cattle. This is our chance to leave them behind!

MALE STUDENT
You mean you want them dead?

LUKE
And I chose you to survive! With Planetfall we can start again. We can build, and breed. We can prosper, we can do anything!

FEMALE STUDENT
We’re going to breed?

LUKE
I’ve designed a mating program. I’ve planned the whole thing.

FEMALE STUDENT
Well then. Shoot me!

She leaves.

LUKE
Stay where you are. Stay where you are I said. Stay where you are! (students start to run out of the room) Stay where you are, that’s an order!

He lowers the gun as most of the students leave the room.

MALE STUDENT
Castor 36? You’re just sick.

He goes too, leaving Luke alone in the room.

LUKE (manically)
Guess that just proves it! I’m cleverer then you! I’m cleverer then everyone! D'you hear me! (shouting and stamping his feet) I’M CLEVER!!

***
NEWS 24 NEWSREADER
The United Nations has issued a directive worldwide, telling urban populations to stay indoors. Those in rural areas are being ordered to stay away from all major cities. There are reports from every country in Europe of thousands of people walking across country to escape. And on the Eastern seaboard of America it’s said to be reminiscent of Dunkirk, with boats taking refugees out into the Atlantic.

AMNN NEWSREADER
With the freeways blocked by ATMOS cars, populations of major cities are now walking across open country to escape the fumes. It is being likened to a Biblical plague. Some are calling this the End of Days.

Donna phones home.

DONNA
Mum? You all right?

SYLVIA
Donna! Where are you sweetheart?

WILF
Is that her?

SYLVIA
Oh, just finish the job. Your granddad’s sealing us in. He’s sealing the windows. Our own house, and we’re sealed in! All those things they said about pollution and ozone and carbon, they’re really happening aren’t they?

DONNA
There’s people working on it, Mum. They’re gonna fix it, I promise.

SYLVIA
Oh, like you’d know, you’re so clever?

DONNA
Oh don’t start. Please, don’t.

SYLVIA
I’m sorry. I wish you were here.

WILF
Now, come on Sylvia, look. That doesn’t help. (he takes the receiver from his daughter) Donna? Where are you?

DONNA
It’s sort of hard to say. You all right?

WILF
Yeah, fighting fit, yeah. Is he with you, the Doctor?

SYLVIA
Oh, the Doctor!

DONNA
No. I’m all on my own.

WILF
Look, you promised he was gonna look after you.

DONNA
He will, Gramps. There’s... something he needs me to do. I just don’t know what.

WILF
Well, I mean, the whole place is covered, the whole of London they’re saying and the whole, the whole world. It’s the scale of it, Donna. I mean, how can one man stop all that?

DONNA
Trust me. He can do it.

WILF
Yeah, well if he doesn’t, you tell him he’ll have to answer to me.

DONNA
I will. Just as soon as I see him, I’ll tell him.

WILF
Huh.

Wilf puts the phone down, and Donna ends the call. Sylvia looks out at the fog engulfed streets.

***
The Doctor snatches a clipboard from the Martha clone.

MARTHA CLONE
There's carbon monoxide, hydrocarbons, nitrogen oxides but 10% unidentified. Some sort of artificial heavy element we can’t trace. You ever seen anything like it?

DOCTOR
Must be something the Sontarans invented. This isn’t just poison, they need this gas for something else. What could that be?

CAPTAIN PRICE
Launch grid online and active.

COLONEL MACE
Positions ladies and gentlemen, Defcon One initiatives in progress.

DOCTOR
What?! I told you not to launch!

COLONEL MACE
The gas is at 60% density, 80% and people start dying, Doctor. We’ve got no choice.

CAPTAIN PRICE
Launching in 60, 59, 58, 57, 56… Worldwide nuclear grid now co-ordinating. 54, 53...

***
The Sontarans are following the events on their ship.

GENERAL STAAL
Hah! The planet is going nuclear! I admire them. The bravery of idiots is bravery nonetheless.

SONTARAN
The operative is in place, sir.

GENERAL STAAL
Commander Skorr! Is the attack squad ready?

COMMANDER SKORR
Ready and eager for battle, sir. We’ve been watching for long enough, it’ll be good to taste blood.

***
DOCTOR
You’re making a mistake, Colonel! For once, I hope the Sontarans are ahead of you.

CAPTAIN PRICE
North America, online. United Kingdom, online. France, online. India, online. Pakistan, online. China, online. North Korea, online. All systems locked and co-ordinated. Launching in 10, 9, 8, 7, 6, 5...

COLONEL MACE
God save us.

CAPTAIN PRICE
...4, 3, 2, 1...

The Martha clone presses ‘No’ on her PDA.

CAPTAIN PRICE
0.

The screen shuts off.

COLONEL MACE
What is it? What happened? Did we launch? Well, did we?

CAPTAIN PRICE
Negative, sir. The launch codes have been wiped, sir. It must be the Sontarans.

COLONEL MACE
Can we override it?

CAPTAIN PRICE
Trying it now, sir.

DOCTOR
Missiles wouldn’t even dent that ship, so why are the Sontarans so keen to stop you? (looking at the clone) Any ideas?

MARTHA CLONE
How should I know?

***
GENERAL STAAL
Now protect the operative.

Sontarans march through the factory. Ross is guarding a deserted corridor with four more soldiers.

ROSS
Stinking out there.

The other soldiers chat. Ross hears something.

ROSS
Shhh! Keep it down lads.

Sontarans come down the corridor.

ROSS (over radio)
Enemy within! At arms! Greyhound 40 declaring absolute emergency. Sontarans within factory grounds, east corridor grid six.

COLONEL MACE (over radio)
Absolute emergency, declaring Code Red. All troops, Code Red!

DOCTOR
Get them out of there!

COLONEL MACE (over radio)
All troops, open fire!

The soldiers try to fire but their guns only click.

ROSS (over radio)
The guns aren’t working. Inform all troops, standard weapons do not work.

The Sontarans shoot at the soldiers, who fall to the ground, screaming.

ROSS (over radio)
Tell the Doctor it’s that Cordolaine signal. He’s the only one who can stop them.

The Sontarans shoot Ross, he falls to the ground. Static from the radio.

COLONEL MACE
Greyhound 40, report. Over. Greyhound 40, report. Greyhound 40, report!

DOCTOR
He wasn’t Greyhound 40, his name was Ross. Now listen to me, and GET THEM OUT OF THERE!

COLONEL MACE
Trap One to all stations. Retreat.

COLONEL MACE
Order imperative, immediate retreat!

***
Soldiers are running everywhere trying to get away.

SOLDIER
Retreat! Retreat!

The Sontarans march out and start shooting everyone down. Chaos everywhere. Private Gray and Private Harris walk out and address a Sontaran.

PRIVATE GRAY/PRIVATE HARRIS
Reporting for duty, sir!

The Sontaran walks past, then turns back and shoots them.

COMMANDER SKORR
This is too easy! Their running like slimebait from a speelfox.

Sontarans continue to shoot UNIT soldiers.

COMMANDER SKORR (laughing)
This isn't war, this is sport!

The factory doors slide down sealing the Sontarans inside.

***
COLONEL MACE
They’ve taken the factory.

DOCTOR
Why? They don’t need it. Why attack now? What are they up to? Times like this, I could do with the Brigadier. No offence.

COLONEL MACE
None taken. Sir Alistair’s a fine man, if not the best. Unfortunately he’s stranded in Peru.

CAPTAIN PRICE
Launch grid back online.

The computer screens turn on to show a map of the world. The Martha clone presses No Launch on her PDA. The screens go black again.

CAPTAIN PRICE
They’re inside the system, sir. It’s coming from within UNIT itself.

COLONEL MACE
Trace it. Find out where it’s coming from, and quickly. Gas levels?

CAPTAIN PRICE
66% in major population areas. And rising.

***
COMMANDER SKORR (over intercom)
Commander Skorr reports victory with many glorious deaths.

Luke Rattigan appears in teleport.

LUKE
Sorry to report, sir, I've failed. They wouldn’t come. The students, they… didn’t have the imagination to believe.

GENERAL STAAL
A pity. We’ve lost our target practice!

LUKE
What do you mean?

GENERAL STAAL
Upon arrival on board this ship, your students would have been shot down. Perhaps they were more clever then you thought.

LUKE (looking hurt)
You promised!

GENERAL STAAL
There was no Planetfall. Castor 36, indeed! We only needed you for installation of the ATMOS system.

LUKE
No, but... I’m on your side! I did everything you wanted! And it’s not ATMOS system, that's a tautology. Just ATMOS.

GENERAL STAAL
Execute him!

Luke presses a button and teleports away.

GENERAL STAAL
A coward’s retreat. Now close all teleport links to Earth. Isolate them, as they perish.

Luke lies on the floor of the teleport pod, crying.

***
COLONEL MACE
Why are they defending the factory only after we were inside?

DOCTOR
Because they wanted UNIT here. You gave them something they needed. Something now hidden inside the factory. Something precious.

COLONEL MACE
Then we’ve got to recover it. This Cordolaine signal thing, how does it work?

DOCTOR
The bullets. It causes expansion of the copper shell.

COLONEL MACE
Excellent. I’m on it.

He gets up and leaves.

DOCTOR
For the billionth time, you can’t fight Sontarans!

He walks out too, and talks quietly to the nearest officer, so that the Martha clone can't hear them.

DOCTOR
Phone. Have you got a phone? I need your mobile, quickly, hurry up!

Someone hands him a mobile and he gets back to Colonel Mace's office to phone Donna.

DONNA
What’s happened, where are you?

DOCTOR
Still on Earth. But don’t worry, I’ve got my secret weapon.

DONNA
What’s that?

DOCTOR
You.

DONNA
Oh. Somehow that’s not making me happy. Can’t you just zap us down to Earth with that remote thing?

DOCTOR
Yeah, I haven’t got a remote, though I really should. But I need you on that ship. That’s why I made them move the TARDIS. I’m sorry, but you’ve got to go outside.

DONNA
But there’s Sonterruns out there.

DOCTOR
Sontarans, but they’ll all be on battle stations right now. They don’t walk around having coffee. I can talk you through it.

DONNA
But what if they find me?

DOCTOR
I know, and I wouldn’t ask, but there’s nothing else I can do. The whole planet is choking, Donna.

DONNA (walking towards the TARDIS door)
What d'you need me to do?

DOCTOR
The Sontarans are inside the factory which means they’ve got a teleport link with the ship, but they’ll have deadlocked it. I need you to reopen the link.

DONNA
But, I can’t even mend a fuse.

DOCTOR
Donna! Stop talking about yourself like that. You can do this. I promise.

Donna opens the TARDIS door to see a Sontaran a few feet away with his back to the TARDIS. She closes the door silently.

DONNA
There's a Sonterrun... Sontaran.

DOCTOR
Did he see you?

DONNA
No, he's got his back to me.

DOCTOR
Right, Donna, listen, on the back of his neck on his collar there's a sort of plug, like a hole. The Probic Vent. One blow to the Probic Vent knocks 'em out.

DONNA
But he's gonna kill me.

DOCTOR
I'm sorry. I swear I'm so sorry. But you've got to try.

She picks up the mallet that the Doctor uses so happily when piloting the TARDIS. She sneaks behind the Sontaran and hits his probic went, knocking him out.

DONNA (triumphant)
Back of the neck!

DOCTOR
Now then you gotta find the external junction feed to the teleport.

DONNA
What... what's it look like?

DOCTOR
A circular panel on the wall. Big symbol on the front, like a, like a letter T with a horizontal line through it. Or, or two Fs back to back.

DONNA
Well, there's a door.

DOCTOR
Should be a switch by the side.

DONNA
Yeah there is. But it's Sontaran-shaped, you need three fingers.

DOCTOR
You've got three fingers.

DONNA
Oh, yeah!

She puts her hand into the pattern and the door slides open.

DONNA
I am through.

DOCTOR (kissing the phone)
Oh, you are brilliant, you are.

DONNA
Shut up. Right. T with a line through it.

Colonel Mace returns to the UNIT base.

DOCTOR
Got to go. Keep the line open!

COLONEL MACE
Counter-attack!

DOCTOR
I said you don't stand a chance!

COLONEL MACE
Positions. That means everyone!

He throws a gas mask to the Doctor.

MARTHA CLONE
You're not going without me!

DOCTOR
Wouldn't dream of it.

***
On the spaceship, Donna hides into a shadowy corner when a troop of Sontarans marches past.

***
Outside of the ATMOS factory, UNIT people gather. They're all wearing gas masks, so does the Doctor. Colonel Mace shows him a gun.

COLONEL MACE
Latest firing stock, what do you think, Doctor?

DOCTOR
Are you my mummy?

COLONEL MACE
If you could concentrate. Bullets with a rad-steel coating, no copper surface. Should overcome the Cordolaine signal.

DOCTOR
But the Sontarans have got lasers! You can't even see in this fog, the night-vision doesn't work.

COLONEL MACE
Thank you Doctor, thank you for your lack of faith. But this time, I'm not listening.

He pulls off the gas mask and addresses his soldiers.

COLONEL MACE
Attention, all troops! Sontarans might think of us as primitive. As does every passing species with an axe to grind. They make a mockery of our weapons, our soldiers, our ideals. But no more! From this point on, it stops. From this point on, the people of Earth fight back and we show them! We show the warriors of Sontar what the human race can do! Trap One to Hawk Major! Go, go, go!

Everyone looks up as a loud sound comes from the sky - the fog starts to clear and we get sight of the Valiant flying above.

COLONEL MACE
It's working! The area's clearing. Engines to maximum!

DOCTOR
It's the Valiant!

COLONEL MACE
UNIT Carrier Ship Valiant reporting for duty, Doctor! With engines strong enough to clear away the fog.

They take off the gas masks.

DOCTOR
Woah, that's brilliant!

COLONEL MACE
Getting a taste for it, Doctor?

DOCTOR
No, not at all. Not me.

COLONEL MACE
Valiant, fire at will!

A bunch of green beams unite and the Valiant fires at the ATMOS factory. At the same time, UNIT soldiers start an attack on the ground too. This time, it's the Sontarans who are overpowered.

COLONEL MACE
East and north secure. Doctor?

He rushes away with the soldiers.

DOCTOR (on the phone)
Donna, hold on. I'm coming.

The Martha clone appears.

MARTHA CLONE
Shouldn't we follow the Colonel?

DOCTOR
Nah, you and me, Martha Jones. Just like old times!

She stops the nuclear launch one more time. The Doctor uses the sonic screwdriver to find their way.

DOCTOR
Alien technology, this way!

***
UNIT and Sontaran soldiers shooting each other everywhere. Commander Skorr is there, without helmet, obviously having a great time.

COMMANDER SKORR
The honour of battle. The glory!

***
The Doctor and the Martha clone head to the basement, following the signal. The place is deserted.

DOCTOR
No Sontarans down here. They can't resist a battle. Here we go.

They enter the clone lab, where the real Martha is still in hypnotic sleep. The Doctor runs to her.

DOCTOR
Ooh, Martha, I'm so sorry. (he checks her pulse) Still alive.

The Martha clone points a gun at him, but he hardly looks at her.

DOCTOR
Am I supposed to be impressed?

MARTHA CLONE
Wish you carried a gun now?

DOCTOR
Not at all.

MARTHA CLONE
I've been stopping the nuclear launch all this time.

DOCTOR
Doing exactly what I wanted. I needed to stop the missiles, just as much as the Sontarans. I'm not having Earth start an interstellar war. You're a triple agent!

MARTHA CLONE
When did you know?

DOCTOR
What, you? Oh, right from the start. Reduced iris contraction, slight thinning of the hair follicles on the left temple. And, frankly, you smell. You might as well have worn a T-shirt saying "clone". Although, maybe not in front of Captain Jack. You remember him, don't you? Cos you've got all her memories. That's why the Sontarans had to protect her, to keep you inside UNIT. Martha Jones is keeping you alive.

He pulls off the device from the real Martha's head. She awakes with a scream. At the same time the clone falls to the ground in agony. The Doctor kicks away the gun that the clone has dropped, then hugs the real Martha.

DOCTOR
It's all right. It's all right, I'm here, I'm here. I've got you, got you.

MARTHA
There was this thing, Doctor, this alien, with this head...

The mobile rings.

DOCTOR
Oh, blimey I'm busy. Got it?

DONNA
Yes. Now hurry up!

DOCTOR
Take off the covering. All the blue switches inside, flick them up like a fusebox. And that should get the teleport working.

Martha looks around and sees the clone, sitting on the ground panting.

MARTHA
Oh, my God. That's me.

***
Commander Skorr walks on a corridor when Colonel Mace comes up behind him.

COLONEL MACE
You will face me, sir!

The Sontaran turns back, pleased for the fight. The Colonel shoots him and he falls to the floor dying, but still seems happy.

COMMANDER SKORR
Wonderful.

***
In the clone lab, the Doctor is working on the teleport while the real Martha sits beside the clone.

MARTHA CLONE
Don't touch me!

MARTHA
It's not my fault. The Sontarans created you. But... you had all my memories.

MARTHA CLONE
You've got a brother, sister, mother and father.

MARTHA
If you don't help me, they're gonna die.

MARTHA CLONE
You love them.

MARTHA
Yes. Remember that?

DOCTOR (shouting from the teleport pod)
The gas! Tell us about the gas.

MARTHA CLONE
He's the enemy!

MARTHA
Then tell me. It's not just poison, what's it for? Martha, please!

MARTHA CLONE
Caesofine concentrate. It's one part of Bosteen, two parts Probic 5.

DOCTOR
Clonefeed! It's clonefeed!

MARTHA
What's clonefeed?

DOCTOR
Like amniotic fluid for Sontarans. That's why they're not invading, they're converting the atmosphere. Changing the planet into a clone world. Earth becomes a great big hatchery. Cos the Sontarans are clones, that's how they reproduce. Give 'em a planet this big, they'll create billions of new soldiers. That gas isn't poison, it's food!

He goes back to work on the teleport.

MARTHA CLONE
My heart... It's getting slower.

MARTHA
There's nothing I can do.

MARTHA CLONE
In your mind, you've got so many plans. There's so much that you wanna do.

MARTHA
And I will. Never do tomorrow what you can do today, my mum says. Cos...

MARTHA CLONE
Cos you never know how long you've got. Martha Jones... All that life.

She dies. The real Martha pulls off her engagement ring from the clone's finger.

DONNA
Doctor.

The Doctor picks up the phone.

DONNA
Blue switches done. (a door slides open and Sontarans march in) But they've found me!

DOCTOR
Now!

He points the sonic screwdriver to the teleport pod, activating it. Donna, who was standing inside the pod on the Sontaran ship, disappears and reappears in the clone lab. She runs to hug the Doctor.

DONNA
Have I ever told you how much I hate you?

DOCTOR
Hold on, hold on. Get off me, get off me! Gotta bring the TARDIS down.

He sonics the teleport and the TARDIS is beamed back down.

DOCTOR
Right, now. Martha, you coming?

MARTHA
What about this nuclear launch thing?

DOCTOR
Just keep pressing N, we want to keep those missiles on the ground.

Donna catches sight of the dead clone.

DONNA
But there’s... two of them.

DOCTOR
Yeah, long story. (all three get inside the teleport pod) Here we go. The old team, back together! Well, the new team.

DONNA
We’re not going back on that ship!

DOCTOR
No, no, no. No. I needed to get the teleport working so that we could get to...

They teleport to the Rattigan Academy.

DOCTOR
...here! The Rattigan Academy, owned by...

Luke points a gun at them.

LUKE
Don’t tell anyone what I did! It wasn’t my fault, the Sontarans lied to me, they...

The Doctor grabs his gun.

DOCTOR
If I see one more gun...

He throws the gun away.

DONNA (to Martha, who wears the Doctor's coat over her hospital-type gown)
You know, that coat, sort of works.

MARTHA
Feel like a kid in my dad’s clothes.

DONNA
Oh, well if you’re calling him dad you’re definitely getting over him.

***
SONTARAN
A human female on board ship. It could only be the Doctor’s work and all the teleport systems have been deadlocked open.

GENERAL STAAL
No matter. Increase the ATMOS devices to maximum. Choke them! Behold, the cloneworld is born.

Alarm blares.

***
Back on Earth, car engines rev. The gas is now also inside the Noble's house. Wilf puts a towel in the gap at the bottom of a door, then he goes to hug Sylvia, who sits on the ground crying.

WILF
Oh, my little girl. Come on, we’ll be all right. We’ll be all right. Donna said so. She promised. Come on, darling. It’s all right.

***
The Doctor begins to assemble a device from things found in Luke's laboratory.

DOCTOR
That’s why the Sontarans had to stop the missiles, they were holding back. Because, caesofine gas is volatile, that's why they had to use you to stop the nuclear attack. Ground-to-air engagement could’ve sparked off the whole thing.

MARTHA
What, like set fire to the atmosphere?

DOCTOR
Yeah. They need all the gas intact to breed their clone army. And all the time we had Luke here in his dream factory. Planning a little trip, were we?

LUKE
They promised me a new world.

DOCTOR
You were building equipment, ready to terraform El Mondo Luko so that humans could live there and breathe the air with this! An atmospheric converter.

***
GENERAL STAAL
Prepare to launch clone pods. We will breed across the surface of the Earth. For the glory of Sontar!

***
The Doctor runs outside with the atmospheric converter.

DONNA
That’s London. You can’t even see it. My family’s in there.

DOCTOR
If I can get this on the right setting...

MARTHA
Doctor, hold on, you said the atmosphere would ignite.

DOCTOR
Yeah, I did, didn’t I?

The Doctor presses a button and a flame shoots up into the sky and the sky ignites. The Doctor crosses his fingers.

DOCTOR
Please, please, please, please, please, please, please...

***
Sylvia and Wilf look out of the window to see the sky aflame. UNIT look up at the burning sky.

***
SONTARAN
General Staal, sir!

GENERAL STAAL
What’s happening?

Alarm blares. The Earth below is engulfed in flame. Then the fire clears to reveal the planet, blue and green as usual.

***
Wilf, Sylvia and their neighbours come out of their houses and celebrate. UNIT soldiers cheer, Captain Price kisses Colonel Mace.

***
LUKE
He’s a genius!

MARTHA
Just brilliant.

DOCTOR
Now we’re in trouble!

He picks up the converter and runs back to the building.

***
GENERAL STAAL
It seems we must revert to Basic Sontaran Stratagem One. We will ravage this planet. Prepare Weapons! Wipe them out! Every last stinking human beast!

***
The Doctor gets inside the teleport pod with the atmospheric converter.

DOCTOR
Right, so... Donna, thank you. For everything. Martha, you too. Oh... so many times. Luke, do something clever with your life.

DONNA
You’re saying goodbye.

DOCTOR
Sontarans are never defeated. They’ll be getting ready for war. And, well, you know, I’ve recalibrated this for Sontaran air, so...

MARTHA
You’re gonna ignite them.

DONNA
You’ll kill yourself.

MARTHA
Just send that thing up, on it’s own. I don’t know... put it on a delay.

DOCTOR
I can’t.

DONNA
Why not?

DOCTOR
I’ve got to give them a choice.

He teleports. Donna and Martha look the empty pod in despair.

***
The Doctor appears on the Sontaran ship.

GENERAL STAAL
Oh, excellent!

DOCTOR
General Staal, you know what this is. But there's one more option. You can go. Just leave. Sontaran High Command need never know what happened here.

GENERAL STAAL
Your stratagem would be wise if Sontarans feared death. But we do not. At arms!

DOCTOR
I'll do it, Staal. If it saves the Earth, I'll do it.

GENERAL STAAL
A warrior doesn't talk, he acts!

DOCTOR
I am giving you the chance to leave.

GENERAL STAAL
And miss the glory of this moment?

SONTARAN VOICE FROM LOUDSPEAKERS
All weapons targeting Earth, sir. Firing in 20.

DOCTOR
I'm warning you!

GENERAL STAAL
And I salute you! Take aim!

DOCTOR
Shoot me, I'm still gonna press this! You'll die, Staal.

GENERAL STAAL
Knowing that you die, too.

VOICE FROM LOUDSPEAKERS
Firing in 15.

GENERAL STAAL
For the glory of Sontar! (he starts chanting) Sontar-ha! Sontar-ha! Sontar-ha!

SONTARANS
Sontar-ha! Sontar-ha! Sontar-ha! Sontar-ha! Sontar-ha! Sontar-ha! Sontar-ha!

DOCTOR
I'll do it!

GENERAL STAAL
Then do it!

***
Back on Earth, Luke is fiddling with the teleport pod.

MARTHA
What are you doing?

LUKE
Something clever.

Standing up, he pushes a key and teleports to the Sontaran ship, at the same time zapping the Doctor back to the Academy.

SONTARANS
Sontar-ha! Sontar-ha! Sontar-ha! Sontar-ha! Sontar-ha!

VOICE FROM LOUDSPEAKERS
10, 9, 8, 7, 6, 5, 4, 3...

The Sontarans stop chanting as they catch sight of Luke.

LUKE
Sontar? Ha!

He pushes the button of the converter.

VOICE FROM LOUDSPEAKERS
...1.

The spaceship explodes before they could launch the strike on Earth.

***
The Doctor appears in the teleport pod at the Rattigan Academy, looking confused. He climbs forward and sits to the edge of the pod, still shocked. Martha runs to him smiling and nestles by his side. Donna walks to them and gives the Doctor a big whack for worrying them so much, then grasps his arm, so relieved that he is alive.

***
Sylvia walks homeward with two big bags.

SYLVIA
Morning.

NEIGHBOUR
Morning.

SYLVIA
Walked all the way, won't catch me driving.

The neighbour gets into her car and pulls off the ATMOS sticker from the rear window. Sylvia enters the house and goes into the kitchen where Donna and Wilf are sitting.

SYLVIA
The streets are half-empty. People still aren't driving. There's kids on bikes all over the place, it's wonderful. Unpack that lot, I'm gonna see if Suzette's all right.

She puts the bags at the kitchen counter and leaves.

WILF
I won't tell her. Best not. Just keep it as our little secret, eh?

DONNA
Yeah.

WILF
And you go with him, that wonderful Doctor. You go and see the stars. And then bring a bit of 'em back, for your old Gramps.

She nods, then gets up to hug him and kisses his head.

DONNA
Love you.

She walks out, fighting back her tears.

***
Donna enters the TARDIS.

MARTHA
How were they?

DONNA
Oh, same old stuff. (she wipes off a tear and tries to sound casual) They're fine. So! You gonna come with us? We're not exactly short of space.

MARTHA
Oh, I have missed all this, but, you know. I'm good here. Back at home. And I'm better for having been away. Besides, (she shows her engagement ring) someone needs me. Never mind the universe, I've got a great big world of my own now!

She walks towards the door, but suddenly it shuts and the TARDIS shakes wildly as it sets to flight. They all cling to different objects to hold their balance. Under the console, the hand in the jar is bubbles wildly.

DOCTOR
What? What!?

MARTHA
Doctor, don't you dare!

DOCTOR
No, no, no! I didn't touch anything! We're in flight, it's not me!

DONNA
Where are we going?

DOCTOR
I don't know, it's out of control!

MARTHA
Doctor, just listen to me! You take me home, take me home right now!