Prime:

(noun) in mathematics, a number which cannot be divided save by itself

or in geometry, the mark indicating such a division: a, a'.

(adjective) of the greatest relevance or significance .

(verb) to prepare or make ready for a particular purpose or operation.

"What's your name?"

"Amelia Pond."

"Oh, that's a brilliant name. Amelia Pond. Like a name in a fairytale."

"And where are you going, little girl?" the man in the funny jumper asks, tipping his hat to her.

"I'm seven," Amelia tells him. "I'm not little."

"Silly old me," the man says, and tips his hat again. "I must have been mistaken, young lady. Only, it's getting dark and I was just wondering what a personage as esteemed as yourself is doing on this road, alone, several miles out from the nearest town."

"I'm looking for someone," Amelia tells him. "He said he would come back soon, but that was yesterday and so I think he must have gotten lost. So I'm looking for him."

"Oh," the man says, twirling his umbrella. "Who was he? Perhaps my companion and I have met him before."

"He never told me his name," Amelia explains. "He said he was the Doctor, but that's not an actual name. So I think he must have been one of the, you know, Lords and Ladies."

"Doctor-" the woman says, sounding alarmed.

"Lords and Ladies," the man interrupts, "what kind of lords, did you say?"

"You know," Amelia says, "the Fair Folk."

"What, like a fairy?" the woman asks, grinning, "With little wings and all?"

"Of course not," Amelia says severely. "The boys don't have wings, they're too big, it's like with bees. And the elves don't have any wings at all, they'd freeze off, and the brownies-"

"Right, sorry, sorry!" the woman says, but she's still smiling.

The man stares at her with the handle of his umbrella pressed up against his mouth. He takes it away, and says, "Who might you be, young lady, that you're looking for the Kindly Ones all on your own like this?"

"I'm Amelia Pond," she says, "and I did bring a bicycle. It just got a flat tire. I had to leave it in the woods."

"Amelia Pond, who brought a bicycle," the man says, shaking her hand, "This is my companion, Ace. And you can call me Professor."

Ace smiles just like she has a secret she'd love to tell, and offers her hand to be shaken.

"Charmed," she drawls. Amelia shakes it. Ace's palm is rough as a dog's paw, nothing like the eerie softness of the Doctor's or the more regular man's-hand feel of the Professor's, and Amelia lets it go only reluctantly.

"Are you two Kindly Ones, then?" she asks. "Only I've been looking a long time, and it is getting dark."

Ace looks at the Professor. The Professor looks at Ace. "I'm feeling rather kindly at the moment," the Professor allows. "Why don't we walk you home, and you can tell us about this Doctor of yours."

So she tells them all about how he came out of a box in her back yard, raggedy as a tramp, and she let him in and gave him food and he threw bread and butter right on to the neighbor's cat, and how he opened up the crack in her wall and then there was this eye that looked at them and then he closed the wall again and told her he'd come back when it was safe, but he still hadn't, and so she had looked all over the village and the woods and the roads and even a few of the ponds and the fish-fingers and custard she had packed for him had gone off so she'd fed them to a big dog and how everyone thought she was a silly little girl and she hated it here and wanted to go away, and even if he couldn't take her away maybe he could take her back to Scotland when her parents were alive, because she misses that almost more than she wants to go anywhere else, and then there's nothing more to say. She takes a deep breath, and wipes her eyes a little.

The Professor is just as serious as when she started talking, and his friend is smiling even wider. But they do look kind, even in the orange-blue evening light that paints everything strange.

"D'you think he's forgotten about me?" she finally asks.

"I couldn't say," the Professor says, "it's all very relative. I, for example, have forgotten more than you would ever be likely to know in the first place, whereas your hypothetical stranger-"

"What the Professor means is no, of course not," Ace says. "You're a very memorable little girl."

"I'm not little, I'm seven," Amelia growls.

"Right, that," says Ace.

"Your Doctor," the Professor says, "will remember you. One way or another."

Amelia feels better.

"Are you from- from Scotland too, then?" she asks. "You sound like me, a bit."

Ace looks very interested.

"Not... not exactly," the man allows. "I've been there from time to time. Picked up a few bad habits from friends, that sort of thing. Nice place, though! Lovely weather. Lovely people." He taps her on the nose. "They make positively top-notch children, I'll tell you that one for free."

Amelia laughs.

"You old cradle-robber," Ace says fondly. "How many of those Scottish kids've you nicked, then?"

"Oh, one or two, here or there." The Professor flips his umbrella into the air, catches it by the question-mark handle.

"Any favorites?" Ace asks.

"There was Jamie," he says, smiling. "Lovely boy. I was barely more than a child then, myself. We had such fun!"

"You were never young," Ace laughs.

"Everyone was young once," the man says, "it's very easy. It's being young twice that's the real trick."

He glances at Amelia. "Would you come away with me, if I invited you? Teach these old hearts to skip along again? Do my spring cleaning, that sort of thing?"

Amelia opens her mouth, closes it. "The Doctor," she says slowly, then: "I don't think I should."

The man nods sharply, as if she's given the only possible answer.

"Good girl. I told you, Ace, top-notch children."

"What were you going to do, with this Doctor of yours?" Ace asks, "If he'd taken you along?"

Amelia thinks about that. "I was thinking he would take me to fairyland," she says, "and we'd have adventures. That's the usual thing when you go off with magical people. That or they make your their slave for ever and ever, but he seemed more like the adventuring sort."

"Aren't you a bit young to go adventuring?" The Professor asks.

"No," Amelia says.

"No," the Professor repeats, amused. "Only I happened to notice that most girls are a bit older, when they go away to seek their respective fortunes. Sixteen, perhaps."

"Oi," Ace says.

"Red Riding Hood wasn't," Amelia says. "She was just like me and she faced down the big bad wolf. And Hansel and Gretel were young, too, and Gretel went and killed the witch, all by herself."

"I thought that both kids did," Ace remarks. "Like, she and her brother pushed the witch in the oven in together."

"That's just what they say so boys won't feel useless," Amelia says. "Really, Gretel tricked the witch into climbing in all on her own, saying she didn't think it was hot enough and the witch should go and check. Then she shut the door."

"Wicked."

It is almost completely night now, and the air is turning cold. Amelia wraps her arms around herself, and wishes she had packed more in her bicycle basket than fish fingers and custard and a broken compass, but she was expecting to take the Doctor back home for lunch before they set out together. Her coat would have been nice, right now.

Ace sees her shiver, and takes off her jacket to give to her. The jacket smells like smoke, when it wraps around Amelia's shoulders, and of a thick wildness just like the stray dog she had fed the Doctor's lunch to, earlier. Wearing it makes Amelia feel huge and monstrous, as if it's magical like the skin of a selkie where you could put it on and be a great big seal; it feels exactly as if she's part of something wilder and grander than herself.

"You're not so big, are you," she says to Ace. "It's all in the clothes, isn't it?"

Ace smiles down at her, slim as a blade against the night. "Don't tell anyone," she says, "they'll never believe you."

They walk. The road is rough in the darkness, and the woods press in around the past like the walls of an endless gullet. Amelia keeps close to her companions.

"Tell us another story," Ace says. "It's getting boring."

"Like what kind?" Amelia asks.

"Something with a girl like you in it," Ace says.

Amelia thinks, and tells her the story of the seven swan princes and their sister, who spun coats out of nettles for a year and a day to break the spell that was trapping them as birds, and how one coat had a sleeve too short and so the youngest brother still had a swan wing, even when he turned back into a prince again. They took the girl back to their kingdom and made her the queen instead of their wicked mother, and she was as steadfast as a queen as she had been a sister. Everyone lived happily ever after except the prince with the one wing, who never forgot the language of birds, and was lonely because of it.

Ace tells them of when she was young, back in Perivale-

"Is that like Camelot?"

"Hardly!"

-and she blew up the art room. Or the chemistry room. Possibly she blew up both of them, she gets vague when questioned on the details. Ace seems like the kind of person who has blown up many more things besides an art or chemistry room.

The Professor tells them stories of when he was younger, and his best friend was a young Scottish boy and they had had all sorts of adventures. He is just telling them about the one with the mechanical yeti when they reach Amelia's front gate and she realizes that now she is home and has to say goodbye.

"Is this your house?" the Professor asks.

"Yes," she says, and just stands there.

"I suppose we had better be getting along," the Professor says.

"You could come in," Amy says. "I could make fish custard."

"Ah, no," the Professor declines. " 'I have promises to keep, and miles to go before I sleep'..."

"Yes," Amelia says again. She's not a little girl, and so she's not going to cry or anything. She bites her tongue to keep her face still.

"What happened to Jamie?" she asks instead. "Did he grow up? Are you still friends?"

Ace cocks her head to one side, her gaze fixing right on the Professor.

"Ah, well, he went home," the Professor says. He looks very old, all of a sudden, and his eyes are very dark. "All good little boys and girls go home eventually, you know."

"I don't, I mean, I wouldn't," Amelia says. "If I ever went traveling, like for real, I'd never ever go back home."

"That's the spirit," Ace says approvingly. "Well behaved women rarely make history."

Amelia grins. "I like that."

"Oh no, you've been reading again," the Professor moans.

"And what if I have?" Ace challenges.

"I put a padlock on the library doors!"

"What doors?"

Amelia laughs, and after a moment the Professor laughs with her.

Ace gives Amelia a fierce hug, and ruffles her hair, and goes to take her jacket back.

"Can't I keep it?" Amelia asks. "I'll trade you my bicycle."

Ace laughs, not unkindly, and tugs it off her. "Not likely," she says, "Jackets like this you can't swap for. You've got to earn 'em."

"I would," she protests.

"You will," Ace says, sounding for a minute just like one of Amy's teachers.

"I will," she repeats.

"Later, Amy," Ace says, and puts the jacket on as she strides away, getting bigger as she goes.

"Good evening, madam," the Professor says, and tips his hat.

"You have to tell me," she blurts out as he turns away, "are you one of the Lords and Ladies too? Do you know my Doctor? Will you tell him I'm waiting?"

The man only smiles his strange smile, and twirls his question-mark umbrella, and follows after his friend.

They vanish into the darkness.

In the Wardrobe Room, Amy finds a kilt. It is frayed and gray around the edges and stained with blood and something purple, and in the sporran next to it is a faded photo of two old men, laughing together... Several things in her mind connect up all at once.

"I thought you said Jamie went home," she says to the Doctor.

The Doctor looks surprised, then sad, then pleased. She wonders if he'll always be this easy to read, this hard to keep up with.

"Some people come back," the Doctor says, and takes the kilt from her, and sets it carefully back on the shelf.