Disclaimer: I own nothing; for fun, not profit; etc. The title and the lines below are taken from Marianne Moore's "Marriage."

Setting/Spoilers: Up through series five's Cold Blood, and more specifically Amy's Choice (and Journey's End, but I'll assume you've seen that if you've seen the former.)

Notes: I love Christkindlmarkts. And Christmas. And Amy Pond and Donna Noble, in varying degrees and different ways.

oOo

See her, see her in this common world,

the central flaw in that first crystal fine experiment,

this amalgamation which can never be more

than an interesting impossibility.

oOo

"So," Amy said, drawing the vowel out. "We're in London."

And indeed they were. Snagging a newspaper discarded on a bench in passing, she opened it up and checked the date.

"So? We're in London," was the Doctor's reply.

"So we're in London ten days before Christmas the year I left," Amy said. "What's the fun in that? Although knowing your abilities to land the TARDIS where you actually mean to, who knows when I'll ever see my own time and place again in the proper combination…"

"Hey!" the Doctor exclaimed, shaking a finger at her. "No running away. You can't leave an old man alone on Christmas. It's rude."

Amy rolled her eyes. "It's only Christmas because you landed during Christmas, and while you may be Mr. Bowties Are Cool - "

("Bowties are cool," muttered the Doctor, adjusting his own.)

" – you're a bit babyfaced to be calling yourself an old man."

The Doctor smiled to himself, but only said, "This is what happens when you let the TARDIS decide. Sometimes where you end up is spectacularly alien, and sometimes it's familiar, but it's always someplace you need to be. The fun is finding out why," he grinned.

Amy looked doubtful. "It's a commercialized shopping madhouse in the center of London."

"It's an adventure!" the Doctor countered, and offered her his arm, which she took after a moment.

"Alright," she conceded. "It's an adventure."

And so it was for a quite a few blocks, until the Doctor ran smack into a woman just off the bus and laden with what was evidently her Christmas shopping, causing her to emit a soft oomph and drop several of her bags.

"Watch it!" she called, all brassy tones to match her hair, which was as flaming as Amy's. "I'll have you know I spent ages looking for some of these things for my daughter, and I'd rather you not ruin her Christmas!"

But the Doctor wasn't paying attention to her words, instead staring at her as though he'd seen a ghost. Appropriate enough for Christmas in London, Amy thought.

"Doctor," she prompted under her breath; and when no response was forthcoming, addressed the woman herself. "You'll have to excuse him, he's all feet and no sense sometimes. Most of the time, actually. I don't know why I let him out," she said, more to the Doctor than anyone else, poking him.

The woman snorted. "No surprises there. Gangly thing, isn't he?"

Before Amy had the chance to voice any opinion, the Doctor suddenly engulfed the woman in a hug, bags and all.

"Oi, oi, oi!" the woman protested again. "Apology accepted, now get off!"

The Doctor withdrew, laughing. "You have a daughter, then! How old?"

She eyed him suspiciously. "Just over a year. Why?"

"I love children," the Doctor replied honestly. "Congratulations."

"Thanks," she returned, eyebrow still raised. "But I really should be getting along, I said I'd be home by half five, and it's nearly that now."

"Of course," the Doctor said warmly. "You and your family have a wonderful Christmas. Oh!" he added almost as an afterthought. "Nothing broken, I hope?"

"No thanks to you, mate," she replied smartly, but she was smiling back at him. "And you as well."

"Excellent. Well then, I won't detain you any longer. It's good to see you."

This caused the woman to frown. "You don't even know me."

The Doctor tilted his head, smiling gently at her. "But can't you see the miracle of it? Of all the millions of Londoners, of all the billions of people in the world, I learned today that you exist," he said simply. "And I think that's reason enough to think it nice to see you."

She stared, for a long moment, as if trying to pluck something from the far recesses of her mind. The Doctor's hand seemed to involuntarily rise in a sort of awkward salutation, seeming almost as though he wanted to brush back a piece of the woman's hair. Just as involuntarily she flinched backward, but her expression morphed into a tangle of amusement and confusion, and the Doctor's hand silently dropped unnoticed, fingers clenching restlessly.

"Blimey, are you always like this?" the woman asked, looking as though she were torn between righteous indignation, complete bemusement, and a smile. "Good luck to your friend, there," she said, giving Amy a smile and a nod.

The Doctor bowed his head in acknowledgment, still wearing that too tender smile. "I'll leave you to it, then, Donna Noble."

He looked again like he'd been sucker punched when the woman – Donna, apparently – watched him with an expression halfway between exasperated and fond before she turned away to leave, never questioning either her reaction or the fact that he knew her name. Amy stepped quietly up to him, and they both watched her disappear into the crowd.

"Old friend?" she inquired, less brazenly than she might have.

The Doctor laughed somewhere in the back of his throat, a sound halfway between tears and happiness. "Yes," he affirmed.

"But she somehow doesn't know you?" Amy pushed, pointing out the obvious.

"No," the Doctor replied so softly she almost couldn't hear his reply, and Amy nearly believed that was going to be the end of that. The Doctor had always had such an open personality around her, so much so that Amy had been long convinced that she could always drag him out of his own mind; but in the last two minutes alone he'd clawed into himself further and more quickly than she'd ever seen him do.

But then, much to her surprise, he continued.

"There was a time not so very long ago I'd nearly managed to convince myself that that woman was going to be alright," he said, "but today, today, I'm telling you that she is. That's something I need you to remember, for your own not-so-very-long-from-now."

Amy looked at him closely. "You've lost me."

He sighed, and said, "You're getting married in the morning," as if that explained everything.

Her eyebrows rose, but she considered that for a moment. There was a tugging at the back of her mind, as if there were something she should remember. "Nope. Still not following you."

So in the end, he threw a lanky arm around her shoulders, and leaned his head close to hers, and his joy nearly radiated off him, making her smile. "Alright, then let's just leave it at the fact that today I discovered that Donna Noble is very well and truly alive, and that makes today a very good day indeed. Shall we celebrate?"

So they did, and ended up spending the day in nineteenth century Munich, wandering through the Christkindlmarkts while eating marzipan and drinking spiced wine. But there was a gnawing sensation at the edges of Amy's mind, and the Doctor was far away with his own wistful thoughts.

Oh, is that who you think you are? The one he trusts? she'd been taunted once, and she'd replied, unflinchingly, Yes.

What's his name? had been the next question, proof of how little she understood of this man.

Amy had asked him once not long after that, and not gotten an answer.

"Names are powerful things," he'd said instead. "And naming is a powerful action."

She thought about the woman they'd met earlier that day, two hundred years from now. She thought about every reaction that woman hadn't been aware she'd had, and everything Amy didn't know about her.

Donna Noble, she mused, and something about it, something indefinable and bigger than she was, made her shiver. There was music on the wind, and she pulled her coat more securely around herself.

You think you're the one girl in the universe to whom the Doctor tells everything?

She was beginning to rethink her answer.