(A shower of snowflakes with teeth heads towards Earth.)

[Park]

(England, 1842. A large hedged area in a suburb, with one big tree and lots of snow on the ground. The other children throw snowballs whilst a lone boy builds a snowman.)

WOMAN: Walter, don't you want to go and play with the other boys and girls? They're very nice.

WALTER: I don't need anyone else.

(A man comes up to her.)

WOMAN: He never talks to anyone. He's so alone. It's not right. It's not healthy.

(The man and woman walk back inside a large building.)

WALTER: I don't want to talk to them. They're silly.

SNOWMAN: They're silly. Don't talk to them. They're silly.

(Walter runs away from the snowman.)

SNOWMAN: Don't need anyone else. I can help you.

WALTER: How?

[Institute]

(50 years later. The young boy is now a sour old man watching men scraping bits of snow off snowmen with nasty toothy grins and into Kilner clip-top jars. He transports the jars back to the GI Institute and goes into a laboratory. There is a large globe on legs three steps up on a dais, which also contains some snow. Electricity crackles around the place.)

SIMEON: The last of the arrivals have been sampled.

SNOWMAN: The great swarm is approaching. As humanity celebrates, so shall it end. Will the final piece be ready?

SIMEON: It's in hand. I serve you in this, as in everything else.

(Walter Simeon spoons the snow from the jars into the globe.)

SNOWMAN: And do you keep my secrets, those men who helped us tonight?

SIMEON: It won't be a problem. I promised to feed them.

[Courtyard]

(Simeon stands on a balcony overlooking the yard full of men.)

WORKER: Beg pardon, Doctor Simeon. It's been a long day. I don't see any food here.

SIMEON: I do.

(Toothy snowmen rear up from the ground.)

WORKER: What is this?

SIMEON: I said I'd feed you. I didn't say who to.

[Rose & Crown]

(A familiar looking young woman gathers empty tankards from the tables and takes the tray outside. There is a toothy snowman in the yard between the inn and the wash house. A man walks past her.)

CLARA: Did you make this snowman?

DOCTOR: No.

CLARA: Well, who did? Because it wasn't there a second ago. It just appeared, from nowhere.

(The Doctor turns and comes back to examine it.)

DOCTOR: Maybe it's snow that fell before. Maybe it remembers how to make snowmen.

CLARA: What, snow that can remember? That's silly.

DOCTOR: What's wrong with silly?

CLARA: Nothing. Still talking to you, ain't I?

DOCTOR: What's your name?

CLARA: Clara.

DOCTOR: Nice name. Clara. You should definitely keep it. Goodbye!

(Clara follows him around the corner.)

CLARA: Oi! Where are you going? I thought we was just getting acquainted.

Those were the days.

(The Doctor leaves. Clara starts to return to the inn, then changes her mind and runs after his brougham carriage. It's not a hansom because the driver is in front, not behind.)

[Carriage]

VASTRA [OC]: How refreshing to see you taking an interest again. Was she nice?

DOCTOR: I just spoke to her.

(This carriage has a telephonic communications device fitted.)

VASTRA [OC]: And made your usual impact, no doubt.

DOCTOR: No, no impact at all. Those days are over.

VASTRA [OC]: You can't help yourself.

[Vastra's study]

VASTRA: It's the same story every time. And it always begins with the same two words.

[Carriage]

DOCTOR: She'll never be able to find me again. She doesn't even have the name. Doctor. What two words?

(Clara's head appears through the hatch in the roof.)

CLARA: Doctor? Doctor who?

[Outside Darkover House]

(A carriage drops off a middle aged man. He is greeted at the door by a servant.)

ALICE: Good evening, sir.

LATIMER: Pond's frozen over. Hasn't frozen since the night

SIMEON: Since the night your children's governess died, a year ago.

ALICE: Doctor Simeon, sir. He insisted on waiting.

LATIMER: She drowned in this very pond.

SIMEON: Which then froze. You didn't find her till a month later, when the ice finally melted.

LATIMER: I recall the incident. It is the sort of thing one remembers.

SIMEON: The ice remembers too.

LATIMER: Who are you? What do you want here?

(Simeon gives him a business card - The Great Intelligence Institute. Memories of the Abominable Snowmen, everyone?)

SIMEON: The pond is yours, Captain Latimer, but what is growing inside it, when it is ready, is ours. Good evening.

[Alleyway]

(A shapely young woman in leather trousers stands in Simeon's path.)

JENNY: Well, Doctor Simeon, you're out very late tonight.

VASTRA: Almost makes you wonder what you've been up to. But then, I have often wondered about the activities of Doctor Simeon and his exceptionally secretive Institute.

SIMEON: Well, I am honoured this evening. The veiled detective and her fatuous accomplice.

JENNY: At your service.

SIMEON: You realise Doctor Doyle is almost certainly basing his fantastical tales on your own exploits? With a few choice alterations, of course. I doubt the readers of The Strand magazine would accept that the great detective is, in reality a woman.

(Simeon lifts Vastra's veil to reveal that she is a Silurian.)

SIMEON: And her suspiciously intimate companion

VASTRA: I resent your implication of impropriety. We are married.

JENNY: More than can be said for you, eh, dear?

VASTRA: Now then. This snow is interesting, don't you think? The ice crystals seem to have a low level telepathic field. Almost as if it can detect and respond to the thoughts and memories of the people around it. Memory snow. Snow that learns.

SIMEON: How fascinating.

VASTRA: I hope it's listening to the right people. It could be a terrible weapon in the wrong hands, don't you think?

SIMEON: I think winter is coming. Such a winter as this world has never known. The last winter of humankind. Do you know why I'm telling you all this?

VASTRA: I am intrigued.

SIMEON: Because there's not a single thing you can do to stop it.

VASTRA: Perhaps I can't, but I know a man who can.

SIMEON: I look forward to meeting him.

(Simeon leaves.)

JENNY: Do you mean the Doctor? He won't help us. He never helps any more, you know that.

VASTRA: Yes, my dear, I do. So pray for a miracle, because I think we are going to need him.

[Outside the Institute]

(Simeon is being watched by a manservant with electronic binoculars. Nearby, the Doctor's carriage is rocking.)

STRAX: They've taken samples from snowmen all over London. What do you suppose they're doing in there?

(The manservant is a Sontaran.)

DOCTOR: This snow is new. Possibly alien. When you find something brand new in the world, something you've never seen before, what's the next thing you look for?

STRAX: A grenade.

DOCTOR: A profit. That's Victorian values for you.

STRAX: I suggest a full frontal assault with automated laser monkeys, scalpel mines and acid.

DOCTOR: Why?

STRAX: Couldn't we at least investigate?

DOCTOR: It's none of our business.

STRAX: Sir, permission to express my opposition to your current apathy?

DOCTOR: Permission granted.

STRAX: Sir, I am opposed to your current apathy.

CLARA [OC]: Let me out!

DOCTOR: Thank you, Strax. And if ever I'm in need of advice from a psychotic potato dwarf, you'll certainly be the first to know.

STRAX: But if the snow is new and alien, shouldn't we be making some attempt to destroy it? Be reasonable.

CLARA [OC] Let me out!

DOCTOR: It is not our problem. Over a thousand years of saving the universe, Strax, you know the one thing I learned? The universe doesn't care.

CLARA [OC]: In this cab. Oi, Doctor! Let me out! Are you listening to me?

DOCTOR: Now, we have a problem of our own to worry about.

CLARA [OC]: Let me out!

[Carriage]

CLARA: Oi!

DOCTOR: Don't worry. No one's going to hurt you.

CLARA: What is that thing?

STRAX: Silence, boy!

DOCTOR: That's Strax. And as you can see, he's easily confused.

STRAX: Silence, girl. Sorry, lad.

DOCTOR: Sontaran. Clone warrior race. Factory produced, whole legions at a time. Two genders is a bit further than he can count.

STRAX: Sir, do not discuss my reproductive cycle in front of enemy girls. It's embarrassing.

DOCTOR: Typical middle child of six million.

CLARA: Who are you?

DOCTOR: It doesn't matter because you're about to forget that you and I ever met.

STRAX: We'll need the worm.

STRAX: Sir.

CLARA: You'll need the what? The worm? What worm?

DOCTOR: Don't worry, it won't hurt, but one touch on your bare skin and you lose the last hour of your memory.

(Strax returns.)

DOCTOR: Where is it?

STRAX: Where's what, sir?

DOCTOR: I sent you to get the memory worm.

STRAX: Did you? When? Who's he? What are we doing here? Look, it's been snowing!

DOCTOR: You didn't use the gauntlets, did you?

STRAX: Why would I need the gauntlets? Do you want me to get the memory worm?

DOCTOR: You.

[By the carriage]

(A short time later, Strax is under the carriage.)

DOCTOR: Well, can you see it?

STRAX: I think I can hear it.

(Clara giggles.)

DOCTOR: Oi, don't try to run away. Stay where you are.

CLARA: Why would I run? I know what's going to happen next and it's funny.

DOCTOR: What's funny?

CLARA: Well, your little pal, for a start. He's an ugly little fella, isn't he?

DOCTOR: Maybe. He gave his life for a friend of mine once.

CLARA: Then how come he's alive?

DOCTOR: Another friend of mine brought him back. I'm not sure all his brains made the return trip!

CLARA: Neither am I.

STRAX: I can see it.

DOCTOR: Ooo! Can you reach it? Have you got it?

STRAX: Got what, sir?

CLARA: Because these are the gauntlets, aren't they?

STRAX: Sir, emergency! I think I've been run over by a cab.

(The Doctor uses the gauntlets to get hold of a large white worm.)

DOCTOR: There you go. One touch and you lose about an hour of your memory. Let it bite you and you could lose decades.

(He puts it into a jar.)

DOCTOR: And you're still not trying to run.

CLARA: I don't understand how the snowman built itself. I'll run once you've explained.

DOCTOR: Clara who?

CLARA: Doctor who?

DOCTOR: Oh, dangerous question.

CLARA: What's wrong with dangerous?

(A snowman appears.)

DOCTOR: The snow emits a low level telepathic field.

CLARA: My snowman.

DOCTOR: It seems to reflect people's thoughts and memories and because it's unusual, somehow it carries a previous shape and

CLARA: No, Doctor. My snowman.

DOCTOR: Ah! Interesting. Well, were you thinking about it?

CLARA: Yes.

(Another one appears, then others.)

DOCTOR: Well, stop. Clara, stop thinking about the snowmen!

(The nearest snowman breaths snowflakes at them.)

DOCTOR: Get down! Clara, listen to me. The snow's feeding off your thoughts.

CLARA: I don't understand.

DOCTOR: You're caught in their telepathic field. They're mirroring you. The more you think about the snowmen, the more they appear. Imagine them melting. Picture it. Picture them melted!

(They get splashed with icy water. The snowmen are gone.)

DOCTOR: Well, very good. Very, very good. Ha!

CLARA: Is that going to happen again?

DOCTOR: Well, if it does, you know what to do about it.

CLARA: Unless I forget.

(The Doctor puts Clara into the carriage.)

DOCTOR: Don't come looking for me. Forget about me. You understand?

CLARA: What about the snow? Shouldn't we be warning people?

DOCTOR: Not my problem. Merry Christmas. Take her back where we found her.

STRAX: Sir.

(Strax drives on, but Clara has already got out of the carriage. She follows the Doctor to -)

[Park]

(Where he climbs over the railings and walks on, whistling Silent Night. Seeing that the coast is clear, he jumps up and grabs a ladder, which he pulls down. Clara hides behind a tree whilst the Doctor climbs the ladder and vanishes. There is a clunk, and the ladder rises up and disappears too. After a moment, Clara comes out and tries to jump for the ladder. She gets it on the second attempt.)

CLARA: Come on.

(She starts to climb. At the top of the ladder, she waves at passers-by, but they do not see or hear her.)

CLARA: Hello. Invisible.

(She is at the base of a spiral staircase. There are footsteps in the air above her.)

CLARA: An invisible staircase.

(The ladder retracts again as she climbs. Soon the rooftops are a long way below.)

[Cloud]

(The Tardis is here. Clara tentatively steps off the staircase into the cloud, goes over and knocks on the door. She hides around the corner when the door opens.)

DOCTOR: Hello? Hello? Hello?

(They both circle the Tardis then Clara heads back down the staircase. The Doctor finds her shawl.)

[Institute]

(More snow samples are fed to the globe.)

SNOWMAN: Tonight the thaw. Tomorrow the snow will fall again, yet stronger. The drowned woman and the dreaming child will give us form at last. Tomorrow the snow will fall and so shall mankind. She is coming.

[Rose & Crown]

(Clara wakes in a bed. She dresses and leaves, carrying a Gladstone bag.)

CLARA: Look at that. Must have thawed in the night.

(The landlord follows her outside.)

CHILCOTT: I'm begging you, Clara. I'm on my knees.

CLARA: Elsie is back this afternoon, and I was only helping out. I've got my own work to get back to.

CHILCOTT: What work? Why won't you ever tell us?

CLARA: You'd never believe me.

(In a carriage, Clara draws down the blinds and changes her clothes.)

[Outside Darkover House]

(Clara steps out of the carriage as a prim and proper young woman, to be met by the maid. She speaks very nicely now, too.)

CLARA: Alice, how smart you look today.

ALICE: The governess should enter by the back door, unless accompanied by the children.

CLARA: And how are the children? Excited about tomorrow?

ALICE: Francesca, same as ever. Digby says he missed you every day. Captain Latimer wants to see you.

CLARA: Of course. Every day?

ALICE: Twice on Saturdays.

CLARA: That's better.

[Study]

CLARA: Captain Latimer.

LATIMER: Ah. Miss Montague, you're back.

CLARA: In time for Christmas. Apologies for my brief absence. Family illness is so unpredictable. You wanted to see me?

LATIMER: Francesca has been having nightmares.

CLARA: Young girls often do.

LATIMER: Every night this week, she says. Won't tell me about them.

CLARA: Perhaps if you asked her in the right way, there's no one she'd rather tell.

LATIMER: Children are not really my area of expertise.

CLARA: They are, however, your children.

LATIMER: You have, if I may say, a remarkable amount of wisdom in these matters, for one so very pretty, Miss Montague. Young, I mean.

CLARA: I'll see to the children now.

[Garden]

(A pair of children are playing chase.)

FRANCESCA: Miss Montague!

DIGBY: Miss Montague, you're back!

CLARA: Ah, ah, ah!

DIGBY: Good morning, Miss Montague.

FRANCESCA: Good morning, Miss Montague.

(Clara shakes their hands.)

CLARA: Good morning, Francesca. Good morning, Digby. Christmas Eve is the most thrilling day, don't you think? Now, what have you two been up to while I've been away?

DIGBY: I did seven drawings and we saw a dead cow.

CLARA: Well, how exciting.

DIGBY: Do your secret voice.

CLARA: Allo, mates.

(Sitting on a bench.)

FRANCESCA: They're not exactly nightmares. Just dreams.

DIGBY: About our old governess. The one who died. She's haunting Frannie from beyond the grave.

CLARA: Haven't you spoken to your father about this?

FRANCESCA: You can't talk about things like that to Daddy.

CLARA: You could try.

DIGBY: Do you want to see where she died?

(They walk around to the front, and the formal pond.)

DIGBY: She fell in there, and then it froze. She was in the ice for days and days. I hated her. She was cross all the time. In Frannie's dream she's still down there, waiting to come back.

CLARA: Everything else has thawed, but this pond is still frozen.

DOCTOR [memory]: The snow is feeding off your thoughts. The more you think about the snowmen, the more they appear.

CLARA: Frannie, this is important. You dream about her. What do you dream?

FRANCESCA: She's cross with me. She says I've been bad, and she's going to come out of the pond and punish me.

CLARA: When?

FRANCESCA: She said she'd come back for Christmas. Tonight.

DIGBY: I think Frannie's gone mad, don't you? I think she needs a doctor.

[Park]

CLARA: Doctor! Doctor!

MAN: What's she looking at?

MAN 2: She's asking for a doctor.

(A crowd gathers to watch Clara jumping in the air.)

CLARA: Doctor!

JENNY: Now then, that's enough noise. We don't want to attract attention, do we?

CLARA: I'm looking for the Doctor. Do you know about him? The Doctor?

JENNY: Doctor who?

[Vastra's home]

STRAX: Do not attempt to escape or you will be obliterated! May I take your coat?

(Vastra is in the conservatory, sitting in a peacock chair and surrounded by exotic greenery.)

JENNY: Sit.

VASTRA: There are two refreshments in your world the colour of red wine. This is not red wine.

JENNY: Madame Vastra will ask you questions. You will confine yourself to single word responses. One word only, do you understand?

CLARA: Why?

VASTRA: Truth is singular. Lies are words, words, words. You met the Doctor, didn't you?

CLARA: Yes.

VASTRA: And now you've come looking for him again. Why?

JENNY: Take your time. One word only.

CLARA: Curiosity.

VASTRA: About?

CLARA: Snow.

VASTRA: And about him?

CLARA: Yes.

VASTRA: What do you want from him?

CLARA: Help.

VASTRA: Why?

CLARA: Danger.

VASTRA: Why would he help you?

CLARA: Kindness.

VASTRA: The Doctor is not kind.

CLARA: No?

VASTRA: No. The Doctor doesn't help people. Not anyone, not ever. He stands above this world and doesn't interfere in the affairs of its inhabitants. He is not your salvation, nor your protector. Do you understand what I am saying to you?

CLARA: Words.

VASTRA: He was different once, a long time ago. Kind, yes. A hero, even. A saver of worlds. But he suffered losses which hurt him. Now he prefers isolation to the possibility of pain's return. Kindly choose a word to indicate your understanding of this.

CLARA: Man.

VASTRA: We are the Doctor's friends. We assist him in his isolation but that does not mean we approve of it. So, a test for you. Give me a message for the Doctor. Tell him all about the snow and what fresh danger you believe it presents, and above all, explain why he should help you. But do it in one word. You're thinking it is impossible that such a word exists, or that you could even find it. Let's see if the gods are with you.

[Tardis]

(The telephone rings. A proper telephone with a curly cord. The Doctor answers it.)

DOCTOR: Yes? What? I'm trying to read.

VASTRA [OC]: Miss Clara and her concerns about the snow.

[Vastra's home]

VASTRA: I gave her the one word test.

DOCTOR [OC]: That's always pointless. What did she say? Well? Well?

VASTRA: Pond.

[Tardis]

VASTRA [OC]: Strax has already suggested where to start investigating.

[Institute]

SNOWMAN; Danger. Danger.

SIMEON: What's wrong?

SNOWMAN: There is danger here. An intelligence. An intelligence beyond anything else in this time and place.

SERVANT: Doctor Simeon, sir. There's someone demanding to see you.

SIMEON: No callers, not in here, not ever. Did he leave his name?

SERVANT: Sir, it's Sherlock Holmes.

(A figure in deerstalker hat, cape, walking cane, and with a Meerschaum pipe, unlit.)

DOCTOR: Oh, nice office. Big globey thing. Now, shut up, don't tell me! I see from your collar stud you have an apple tree and a wife with a limp. Am I right?

SIMEON: No.

DOCTOR: Do you have a wife?

SIMEON: No.

DOCTOR: Bit of a tree? Bit of a wife? Some apples? Come on, work with me here.

SIMEON: I enjoy The Strand magazine as much as the next man, but I am perfectly aware that Sherlock Holmes is a fictional character. Get out!

DOCTOR: Do you have a goldfish named Colin?

SERVANT: No.

DOCTOR: Thought not. Now, ooo. I see this is one of your business cards. It says so on the front.

SIMEON: Who are you, and What are you doing here?

DOCTOR: This. Wakey, wakey!

(The Doctor hits the globe with his cane.)

SIMEON: That is highly valuable equipment. You must step away now.

SNOWMAN: We are the Intelligence.

DOCTOR: Ooo. Talking snow. I love new things.

SNOWMAN: You are not of this world.

DOCTOR: Takes one to snow one. Right, let's see. Multi-nucleate crystalline organism with the ability to mimic and mirror what it finds. Looks like snow. Isn't snow.

SIMEON: You must leave here now.

DOCTOR: Shut up, I'm making deductions. It's very exciting. Now, what are you, eh? A flock of space crystals? A swarm? The snowmen are foot soldiers, mindless predators. But you, you're the clever one. You're Moriarty. So, you turn up on a planet, you generate a telepathic field to learn what you can, and when you've learnt enough, what do you do? You can't conquer the world using snowmen. Snowmen are rubbish in July. You'll have to be better than that. You'll have to evolve.

(During this speech, the Doctor has sonicked the doors locked.)

SERVANT [OC]: Sir, it appears to be stuck!

SIMEON: What have you done? Have you locked the doors?

DOCTOR: You need to translate yourself into something more, well, human.

SIMEON: Kick it down.

DOCTOR: To do that you'd need a perfect duplicate of human DNA in ice form. Where do you find that?

SERVANT [OC]: Sir?

SIMEON: Get in here, quickly!

SERVANT [OC]: I've got a master key somewhere, sir.

DOCTOR: Now, let's see. Most opened file, most viewed page.

(The Doctor tosses Simeon's scrap book in the air, and it lands open at a newspaper cutting headed Tragedy at Darkover House.)

DOCTOR: You know, you really should delete your history. Governess frozen in pond. Gotcha!

SERVANT [OC]: Got it, sir!

SIMEON: Get in here! Take him downstairs.

(But the Doctor has already left by the French windows.)

[Outside Darkover House]

DOCTOR: Body frozen in a pond. The snow gets a good long look at a human being, like a full body scan. Everything they need to evolve. Pond. Good point, Clara. What are you doing here?

(Strax is holding an alien weapon.)

STRAX: Madame Vastra wondered if you were needing any grenades?

DOCTOR: Grenades?

STRAX: She might have said help.

DOCTOR: Help for what?

STRAX: Well, your investigation.

DOCTOR: Investigation? Who says I'm investigating? Do you think I'm going to start investigating just because some bird smiles at me? Who do you think I am?

STRAX: Sherlock Holmes.

DOCTOR: Don't be clever, Strax. It doesn't suit you.

STRAX: Sorry, sir.

DOCTOR: I'm the clever one, you're the potato one.

STRAX: Yes, sir.

DOCTOR: Now go away.

STRAX: Yes, Mister Holmes.

DOCTOR: Oi! Shut up. You're not clever or funny and you've got tiny little legs!

(He sees Clara watching from a window. She waves, and he waves back.)

DOCTOR: Okay, just tell her you're leaving, you're not going up. Leaving. Not going up.

(But his hand says five and gives the thumbs up.)

DOCTOR: What was that about? Five minutes, where did that come from? You.

(He leaves the pond, and the ice begins to crack.)

[Outside the garden walls]

(Strax, Jenny and Vastra watch a carriage pull up.)

STRAX: It's the human male from the Institute. What's he doing here? Suggest we melt his brain using projectile acid fish, and then interrogate him. Other way round.

[Bedroom]

FRANCESCA: Am I going to have the nightmare tonight?

CLARA: Definitely not.

FRANCESCA: How do you know?

CLARA: Because someone's coming to help.

FRANCESCA: Who?

CLARA: You wouldn't believe me if I told you.

FRANCESCA: Is it one of your stories? Your definitely true ones?

CLARA: Ha! All my stories are true.

DIGBY: Like how you were born behind the clock face of Big Ben?

CLARA: Accounting for my acute sense of time.

FRANCESCA: And you invented fish.

CLARA: Because I dislike swimming alone.

DIGBY: So what's this one?

CLARA: There's a man called the Doctor. He lives on a cloud in the sky, and all he does, all day every day, is to stop all the children in the world ever having bad dreams.

FRANCESCA: I've been having bad dreams.

CLARA: He's been on holiday. But I am confident he has now returned to work. And as a matter of fact, he's right here.

(The candle flickers as the door opens.)

CLARA: Aren't you, Doctor?

(A woman made of ice enters. The children scream.)

CLARA: Bloomin' hell!

GOVERNESS: The children have been very naughty.

CLARA: Get back. Now. Quickly.

DIGBY: You're doing your other voice.

CLARA: Yes love, did you notice?

GOVERNESS: Naughty, naughty children.

CLARA: Run!

[Schoolroom]

DIGBY: What do we do?

CLARA: Frannie, Frannie, imagine her melting.

FRANCESCA: What?

CLARA: In your head. Melt her.

FRANCESCA: I can't!

GOVERNESS [OC]: I'm getting impatient!

(She forces the adjoining door open.)

GOVERNESS: You have been very naughty!

DIGBY: What about the man? You said the man was here, the cloud man.

CLARA: Well, he's not, is he?

DIGBY: Where's the Doctor?

CLARA: I don't know!

PUNCH: Doctor? Doctor? Doctor who?

(The Punch puppet aims the sonic screwdriver at the Ice Governess, who shatters.)

DOCTOR: That's the way to do it.

(Punch kisses the Doctor.)

DOCTOR: Oi. Ow.

(Outside the grounds, Simeon activates a device on the back of his carriage that sends snow into the air around the house.)

FRANCESCA: Where did she go? Will she come back?

DOCTOR: No, don't worry. She's currently draining through your carpet. New setting. Anti-freeze. And you're very welcome, by the way.

CLARA: I'm very grateful. I knew you'd come.

DOCTOR: No, you didn't, because I don't. Because this isn't the sort of thing I do any more. Next time you're in trouble, don't expect me to

(The Doctor is distracted by his reflection in a mirror.)

CLARA: What is it? What's wrong?

DOCTOR: Sorry, it's just. Didn't know I'd put it on.

(He straightens his bow tie, while ice forms on the windows.)

DOCTOR: Old habits

CLARA: It's cooler.

DOCTOR: Yeah, it is, isn't it? It is very cool. Bow ties are cool.

CLARA: No, the room. The room's getting colder.

(A bulge forms in the carpet.)

DIGBY: She's coming back!

FRANCESCA: What's she going to do? Is she going to punish me?

DOCTOR: Er, er, she's learnt not to melt. Of course, she's not really a governess, she's just a beast. She's going to eat you. Run.

[Entrance hall]

(They run down the stairs.)

LATIMER: Children, what is the expla. Who the devil are you? What are you doing in my house?

DOCTOR: It's okay. I am your governess' gentleman friend, and we've just been upstairs kissing!

ALICE: Captain Latimer. In the garden, there's snowmen! And they're just growing out of nowhere, all by themselves. Look!

(Alice runs to answer the front door.)

VASTRA: Good evening. I'm a Lizard Woman from the Dawn of Time, and this is my wife.

(Alice screams and runs back into -)

STRAX: This dwelling is under attack. Remain calm, human scum.

(Alice screams and faints.)

DOCTOR: So, any questions?

LATIMER: You have a gentleman friend?

DOCTOR: Vastra, what's happening?

VASTRA: The snow is highly localised, and on this occasion not naturally occurring.

JENNY: It's coming out of that cab parked by the gates.

STRAX: Sir, one pulver grenade would blow these snowmen to smithereens.

DOCTOR: They're made of snow, Strax. They're already smithereens. See, Clara? Our friends again.

LATIMER: Clara? Who's Clara?

DOCTOR: Your current governess is in reality a former barmaid called Clara.

GOVERNESS: That's the way to do it!

DOCTOR: Meanwhile your previous governess is now a living ice sculpture impersonating Mister Punch. Jenny, what have you got?

(Jenny throws a little ball that creates a forcefield at the top of the stairs.)

JENNY: That should hold it.

STRAX: Sir, this room. One observational window on the line of attack and one defendable entrance.

DOCTOR: Right, everyone in there. Now. Move it. You, carry her.

VASTRA: Nice to see you off your cloud and engaging again.

DOCTOR: I'm not engaging again, I'm under attack.

VASTRA: You missed this, didn't you?

(The governess batters against the forcefield.)

DOCTOR: Shut up.

[Study]

DOCTOR: Strax, how long have we got?

STRAX: They're not going to attack. They made no attempt to conceal their arrival. An attack force would never abandon surprise so easily, and they're clearly in a defence formation.

DOCTOR: Way, aye, aye. Well done, Straxie. Still got it, buddy.

(And kisses the Sontaran on the top of the head.)

STRAX: Sir, please do not noogie me during combat prep.

DOCTOR: So there's something here they want.

CLARA: The ice woman.

DOCTOR: Exactly.

JENNY: Why's she so important?

DOCTOR: Because she's a perfect duplication of human DNA in ice crystal form. The ultimate fusion of snow and humanity. To live here, the snow needs to evolve and she's the blueprint. She's what they need to become. When the snow melted last night, did the pond?

CLARA: No.

DOCTOR: Living ice that will never melt. If the snow gets hold of that creature on the stairs, it will learn to make more of them. It will build an army of ice. And it will be the last day of humanity on this planet.

(The doorbell rings.)

DOCTOR: Stay here.

[Entrance hall]

DOCTOR: Oi, I told you to stay in there.

CLARA: Oh, I didn't listen.

DOCTOR: You do that a lot.

CLARA: It's why you like me.

DOCTOR: Who said I like you?

(Clara kisses the Doctor.)

CLARA: I think you just did.

DOCTOR: You kissed me.

CLARA: You blushed. And we just. Shut up.

(The Doctor opens the front door.)

SIMEON: Release her to us. You have five minutes.

(Simeon turns away and the Doctor closes the door.)

DOCTOR: We need to get her out of here but keep her away from them.

CLARA: How?

(The Doctor takes an umbrella from the stand.)

DOCTOR: With this. Do I always have to state the obvious?

LATIMER: Those creatures outside, what are they?

DOCTOR: No danger to you, as long as I get that thing out of here. You, in there, now.

(He goes up the stairs and sonicks the forcefield.)

CLARA: What are you doing?

DOCTOR: Between you and me, I can't wait to find out.

(The forcefield turns off then reforms behind him and Clara.)

DOCTOR: Right, if you look after everyone here, then I can. Clara!

CLARA: Doctor.

(They duck under the Governesses arms and run up the stairs.)

DOCTOR: That was stupid.

CLARA: You were stupid, too.

DOCTOR: I'm allowed. I'm good at stupid.

GOVERNESS: That's the way to do it!

CLARA: Why does she keep saying that?

DOCTOR: Mirroring. Random mirroring. We need to get on the roof.

CLARA: This way!

DOCTOR: No, I do the hand grabbing. That's my job. That's always me!

[Roof]

DOCTOR: Come on, quickly! What are you doing?

CLARA: My bustle is stuck.

DOCTOR: Your bustle?

(The Doctor pulls Clara through the window. She lands on top of him.)

DOCTOR: You're going to have to take those clothes off. I didn't mean.

CLARA: I know. I understand, I do.

DOCTOR: Good.

CLARA: Now, what's the plan?

DOCTOR: Who said I've got a plan?

CLARA: Course you've got a plan. You took that.

DOCTOR: Maybe I'm an idiot.

CLARA: You're not. You're clever. Really clever.

DOCTOR: Are you?

(He throws Clara the umbrella.)

DOCTOR: If I've got a plan, what is it? You tell me.

GOVERNESS: That's the way to do it!

CLARA: Is this a test?

DOCTOR: Yes.

CLARA: What will it do to us?

DOCTOR: Kill us.

GOVERNESS: That's the way to do it!

(The Governess turns to snow to get through the window.)

DOCTOR: So, come on then. Plan. Do I have one?

CLARA: Oh, I know what your plan is. I knew straight away.

DOCTOR: No, you didn't.

CLARA: Course I did.

DOCTOR: Show me.

CLARA: Why should I?

DOCTOR: Because we'll be dead in under thirty seconds. Do I have a plan?

CLARA: If we'd been escaping, we'd be climbing down the building. If we'd been hiding, we'd be on the other side of the roof. But no, we're standing right here.

DOCTOR: So?

CLARA: So!

(Clara reaches up with the umbrella and pulls the ladder down. The Governess is reforming on the roof.)

CLARA: After you.

DOCTOR: After you.

CLARA: After you, I'm wearing a dress. Eyes front, soldier!

DOCTOR: My eyes are always front!

CLARA: Mine aren't.

DOCTOR: Stop it.

CLARA: No. I understand you're the previous governess. I regret to inform you the position is taken. Goodnight.

(Clara taps the ladder, steps onto it and is raised into the air.)

[Staircase]

CLARA: So you can move your cloud? You can control it?

DOCTOR: No. No one can control clouds, that would be silly. The wind, a little bit.

CLARA: She's following us.

DOCTOR: That's the idea. Keep her away from the snow. So. Barmaid or governess, which is it?

CLARA: That thing is after us, and you want a chat?

DOCTOR: Well, we can't chat after we've been horribly killed, can we?

CLARA: How did we get up so high so quick?

DOCTOR: Clever staircase. It's taller on the inside.

CLARA: What am I standing on, what's this made of?

DOCTOR: Super dense water vapour. Should keep her trapped for the moment.

[Cloud]

CLARA: Do you actually live up here on a cloud, in a box?

DOCTOR: I have done for a long time now.

CLARA: Blimey, you really know how to sulk, don't you?

DOCTOR: I'm not sulking.

CLARA: You live in a box!

DOCTOR: That's no more a box than you are a governess.

CLARA: Oh, spoken like a man. You know, you're the same as all the rest. Sweet little Clara, works at the Rose And Crown, ideas above her station.

[Tardis]

CLARA: Well, for your information, I'm not sweet on the inside, and I'm certainly not

(The Doctor turns on the Tardis light. He's been redecorating, and I like it. A classic six sided free-standing console with time rotor and no nasty pseudo-organic rubbish.)

CLARA: Little.

DOCTOR: It's called the Tardis. It can travel anywhere in time and space. And it's mine.

CLARA: But it's. Look at it, it's

DOCTOR: Go on, say it. Most people do.

(Clara does the traditional circuit of the outside and returns.)

CLARA: It's smaller on the outside.

DOCTOR: Okay, that is a first.

CLARA: Is it magic? Is it a machine?

DOCTOR: It's a ship.

CLARA: A ship?

DOCTOR: Best ship in the universe.

CLARA: Is there a kitchen?

DOCTOR: Another first.

CLARA: I don't know why I asked that. It's just, I like making soufflés.

DOCTOR: Soufflés?

CLARA: Why are you showing me all this?

DOCTOR: You followed me, remember? I didn't invite you.

CLARA: You're nearly a foot taller than I am. You could've reached the ladder without this. You took it for me. Why?

(She throws the umbrella to him.)

DOCTOR: I never know why. I only know who.

(The Doctor holds up a key, then puts it in Clara's hand.)

CLARA: What's this?

DOCTOR: Me. Giving in.

CLARA: I don't know why I'm crying.

DOCTOR: I do. Remember this. This right now, remember all of it. Because this is the day. This is the day. This is the day everything begins.

(But as he starts to crank up the console, the Governess grabs Clara from behind and drags her outside. She drops the key.)

DOCTOR: Clara! Clara!

[Cloud]

CLARA: Get off of me!

DOCTOR: Water vapour doesn't stop ice. I should've realised.

CLARA: Get off!

DOCTOR: Let her go. Let her go now! Now!

CLARA: Get off of me!

DOCTOR: No. Clara!

(The Governess and Clara fall backwards off the cloud.)

DOCTOR: Nooooo!

[Study]

(There is a Whumph! outside.)

VASTRA: What was that?

JENNY: It's Clara.

(Vastra's steampunk style tricorder does not give good news. No life signs detected.)

LATIMER: Dear God. Oh, dear God. Where did she fall from? We have to get her inside.

VASTRA: Those things will kill you.

LATIMER: She's hurt.

VASTRA: She's dead.

(The sound of the Tardis is heard.)

LATIMER: What is that? What is happening?

(The Tardis materialises around Clara.)

VASTRA: He's bringing her in.

(A short time later, Clara is lying on a table while Strax uses a device. The Tardis is parked in the corner of the room.)

LATIMER: That green woman said she was dead. How can she be alive now?

STRAX: This technology has capacities and abilities beyond anything your puny human mind could possibly understand. Try not to worry.

[Tardis]

(The Doctor is scanning the ice fragments that were around Clara.)

VASTRA: Isn't the creature still a danger? It could reform.

DOCTOR: No, not in here.

VASTRA: Then you should be with Miss Clara.

DOCTOR: She's going to be fine. I know she is. She has to be.

STRAX: Doctor, her injuries are severe. That equipment will bring back anyone for a while, but long term

DOCTOR: It was my fault. I am responsible for what happened to Clara. She was in my care.

VASTRA: What is the point of blaming yourself?

DOCTOR: None. Because she's going to live.

[Study]

(The Doctor hands a London Underground souvenir lunchbox to Jenny. It rattles.)

DOCTOR: Hey. Hello.

CLARA: They all think I'm going to die, don't they?

DOCTOR: And I know you're going to live.

CLARA: How?

DOCTOR: I never know how. I just know who.

(He gives her the key again and kisses her hand.)

CLARA: The green lady. She said you were the saver of worlds once. Are you going to save this one?

DOCTOR: If I do, will you come away with me?

CLARA: Yes.

DOCTOR: Well then. Merry Christmas.

(He straightens his bow tie, takes back the lunch box and answers the door to Simeon.)

[Front door]

DOCTOR: I have in my hand a piece of the Ice Lady. Everything you need to know about how to make ice people. Is that what you want? See you at the office.

[Tardis]

VASTRA: So then, Doctor, saving the world again? Might I ask why? Are you making a bargain with the universe? You'll save the world to let her live?

DOCTOR: Yes. And don't you think, after all this time and everything I've ever done, that I am owed this one?

VASTRA: I don't think the universe makes bargains.

DOCTOR: It was my fault.

VASTRA: Well then. Better save the world.

[Institute]

(Vastra and the Doctor are waiting when Simeon enters.)

SIMEON: You promised us something. Have you brought it?

DOCTOR: Big fella here's been very quiet while you've been out. Which is only to be expected, considering who he really is. Do you know what this is, big fella?

(The Doctor holds up the lunch box.)

SNOWMAN: I do not understand these markings.

DOCTOR: A map of the London Underground, 1967. Key strategic weakness in metropolitan living, if you ask me, but then I have never liked a tunnel.

SNOWMAN: Enough of this. We are powerful, but on this planet we are limited. We need to learn to take human form.

(The Doctor uses the sonic screwdriver, and the Snowman's voice rises in pitch.)

SNOWMAN: The Governess is our most perfect replication of humanity.

VASTRA: What's happening to its voice?

DOCTOR: Just stripping away the disguise.

SNOWMAN: No, stop! Stop that. Cease, I command you.

VASTRA: It sounds like a child.

DOCTOR: Of course it sounds like a child. It is a child. Simeon as a child. The snow has no voice without him.

SNOWMAN: Don't listen to him, he's ruining everything.

DOCTOR: How long has the Intelligence been talking to you?

SIMEON: I was a little boy. He was my snowman. He spoke to me.

SNOWMAN [memory]: They're silly.

DOCTOR: But the snow doesn't talk, does it. It's just a mirror.

WALTER [memory]: I don't want to talk to them. They're silly.

SNOWMAN [memory]: They're silly.

DOCTOR: It just reflects back everything we think and feel and fear.

WALTER [memory]: I don't need anyone else.

SNOWMAN [memory]: Don't need anyone else.

DOCTOR: You poured your darkest dreams into a snowman and look, look what it became.

VASTRA: I don't understand.

DOCTOR: It's a parasite feeding on the loneliness of a child and the sickness of an old man. Carnivorous snow meets Victorian values and something terrible is born.

SNOWMAN: We can go on and do everything we planned.

DOCTOR: Oh yes, and what a plan. A world full of living ice people. Oh dear me, how very Victorian of you.

SIMEON: What's wrong with Victorian values?

(Simeon grabs the lunch box and opens it.)

DOCTOR: Ah, ah, ah. Are you sure?

SIMEON: I have always been sure.

(The memory worm in the box bites him.)

DOCTOR: Good. I'm glad you think so, since your entire adult life is about to be erased. No parasite without a host. Without you, it will have no voice. Without the governess, it will have no form.

SNOWMAN: What, what, what's happening? What's happening? What did you do?

DOCTOR: You've got nothing left to mirror any more. Goodbye.

SNOWMAN: What did you, did you.

(The snow suddenly fills the globe and its voice deepens again.)

SNOWMAN: Did you really think it would be so easy?

DOCTOR: That's not possible. How is that possible?

VASTRA: Doctor?

[Study]

JENNY: They're growing! The snowmen are growing!

LATIMER: What should we do?

[Institute]

DOCTOR: But you were just Doctor Simeon. You're not real. He dreamed you. How can you still exist?

SNOWMAN: Now the dream outlives the dreamer and can never die. Once I was the puppet.

(Simeon is reanimated as an icy ghoul.)

SNOWMAN: Now I pull the strings! I tried so long to take on human form. By erasing Simeon, you made space for me. I fill him now.

(Simeon knocks Vastra aside and grabs the Doctor.)

SNOWMAN: More than snow, more than Simeon. Even this old body is strong in my control.

DOCTOR: Argh!

SNOWMAN: Do you feel it? Winter is coming!

(His touch starts to freeze the Doctor's skin.)

DOCTOR: Argh!

SNOWMAN: Winter is coming!

[Study]

STRAX: No, you must fight. Hang on and fight, boy. You can do it.

CLARA: Captain Latimer. Your children. They're afraid. Hold them.

LATIMER: It's not really my area.

CLARA: It is now.

(A single tear runs down from Clara's eye. Outside, thunder rends the snowstorm and turns it into rain.)

[Institute]

(The snow globe is filled with melt water. Simeon leaps off the Doctor.)

SNOWMAN: What's happening?

VASTRA: Doctor, the globe. It's turning to rain. All of it, the snow, look.

(Simeon dies.)

VASTRA: He's dead. What happened?

DOCTOR: The snow mirrors, that's all it does. It's mirroring something else now. Something so strong, it's drowning everything else.

(The Doctor opens a window and holds out his hand.)

DOCTOR: There was a critical mass of snow at the house. If something happened there

(They both taste the rain.)

VASTRA: It's salty. Salt water rain.

DOCTOR: It's not raining. It's crying. The only force on Earth that could drown the snow. A whole family crying on Christmas Eve.

[Study]

(The Tardis materialises.)

STRAX: I'm sorry. There was nothing to be done. She has moments only.

DOCTOR: We saved the world, Clara, you and me. We really, really did.

CLARA: Are you going back to your cloud?

DOCTOR: No more cloud. Not now.

CLARA: Why not?

DOCTOR: It rained.

CLARA: Run. Run, you clever boy. And remember.

(The clock chimes midnight as Clara dies.)

DIGBY: It's Christmas. Christmas Day.

[Graveyard]

(Captain Latimer is with his children by the graveside.)

VASTRA: And what about the Intelligence? Melted with the snow?

DOCTOR: No, I shouldn't think so. It learned to survive beyond physical form.

JENNY: Well, we can't be in much danger from a disembodied Intelligence that thinks it can invade the world with snowmen.

VASTRA: Or that the London Underground is a key strategic weakness.

DOCTOR: The Great Intelligence. Rings a bell. The Great Intelligence.

(He walks forward to the grave as the family leave.)

JENNY: Doctor?

(The gravestone has already been carved and put in place.)

DOCTOR: I never knew her name. Her full name.

OSWIN [memory]: Oswin Oswald. Junior Entertainment Manager, Starship Alaska.

DOCTOR: Soufflé girl. Oswin. It was her.

OSWIN [memory]: Run, you clever boy.

CLARA [memory]: Run, you clever boy.

OSWIN [memory]: And remember.

CLARA [memory]: And remember.

DOCTOR: It was soufflé girl again. I never saw her face the first time with the Daleks, but her voice, it was the same voice.

JENNY: Doctor?

DOCTOR: The same woman, twice. And she died both times. The same woman!

VASTRA: Doctor, please, what are you talking about?

DOCTOR: Something's going on. Something impossible, something. Right, you two stay here. Stay right here. Don't move an inch.

VASTRA: Are you coming back?

DOCTOR: Shouldn't think so!

VASTRA: But where are you going?

DOCTOR: To find her. To find Clara. Ha ha ha!

JENNY: But Clara's dead. What's he talking about, finding her?

(Clara Oswin Oswald. Remember me, we shall meet again. Born November 23 1866, died December 24, 1892.)

VASTRA: I don't know, but perhaps the universe makes bargains after all.

(Same graveyard, over a hundred years later and somewhat overgrown.)

GIRL [OC]: Where are you going?

CLARA: Short cut.

GIRL: Through there? I hate this place! Don't you think it's creepy?

CLARA: Nah. I don't believe in ghosts.

[Tardis]

DOCTOR: Clara Oswin Oswald. Watch me run.