Ten years have passed. Thirty-year-old Rose Tyler lives an ordinary, uneventful life in South London. She takes the bus to work every morning and home every evening. She lives alone. Or at least, that's how it should be...

But, as we all know, things don't always turn out as they're supposed to. The reality is, there is no Rose Tyler. She doesn't take the bus to work every morning and home every night, she doesn't live alone, and she certainly doesn't live an ordinary, uneventful life.

In reality, if one has done as many things as Rose Tyler had done, has seen as many things as she had seen, the things one has seen and done make it very hard for anything to be ordinary again.

Particularly when one has done something like what Rose Tyler did.

Strange things, often terrifying things, surrounded the Doctor. He made sure that anyone who decided to travel with him was well aware of that. It wasn't his fault, of course. It was just one of the things that came with being the last of the Time Lords and the protector of the whole universe.

Right now, strange things were happening that even he couldn't begin to understand. There were footprints where there shouldn't be footprints, troubles that were resolved before he got there to resolve it, trails through time that he hadn't left. These traces were like signatures, someone taking some great, otherworldly pen and signing their name to their work.

He'd only seen this one time before, and it hadn't really been anything like this. Leaving the past a message was different from actively repairing the timestream. The strangest thing about it, however, was that he was just as busy as he'd been before.

"If I'm still working as hard as always," he said to Leta as he stood next to the TARDIS by the edge of the city, "and someone else is coming in and fixing up time, then that means there's a lot more trouble than there used to be."

"Sounds like you should be grateful for the help," Leta observed. "If there's enough trouble to keep two protectors busy, it's probably way too much for one to handle."

"I know," he said, frowning. "It's just strange, that's all. It doesn't make sense. At least I try to cover my tracks. It's as if—as if this person wants to be found, wants to be followed."

"And is that so strange? Maybe whoever it is likes danger. You like danger. In fact, I've never understood why you don't sometimes let the aliens hunt you down when you're bored, just for the sake of having something to do."

"I have more dangerous enemies," he said cooly. "And besides, it would be stupid to do that. I'm not thick, unlike whoever's doing this. They have to be thick, to leave such glaring trails behind—oh, now, that's not very nice, is it?"

"Nope," she said. "It's usually rude to call someone thick, you know."

"Yes, well..." He frowned and thought. then shook his head. "Check out the city. find out what you can. I'm going for a walk."

"Fantastic," Leta muttered, just loudly enough that he managed to make it out. "All the aliens chase me."

"Stop whining," he said amiably, and walked away towards the cliffs.

As he walked along the edge that fell into the sea, he stumbled, quite by accident, on something else strange. It was in the form of a girl, standing on the cliff, her hair lifted by the wind. A girl who, by all the laws he had thought he'd known, should not exist.

She was facing away, looking out at the sea, but he was sure he knew her. Suddenly, she turned. She saw him, and her narrowed eyes wen wide. Without another glance, she ran along the edge of the cliffs until she reached the city.

He ran after her, but when he reached the street, she was gone. Simply gone, not as if she'd hidden, but as if she'd vanished off the face of the planet.

He looked around, walked up to a woman, and asked, "Have you seen a blonde girl, not quite as tall as I am?"

The woman shook her head. He sighed and thanked her, then walked down the street, thinking. Where had she gone? She couldn't have just disappeared. Unless he'd only imagined her...that seemed likely, as she shouldn't even be here. Unless he was here, somewhere else. But he'd never been here before, which meant that even if he was here, she shouldn't be. Unless he was going to go back, get her, and come here where he had been before.

"Oh, fantastic," he muttered. "Now I'm just giving myself a headache." He ran his fingers through his untidy hair and was so distracted that he walked into a girl carrying groceries.

She fell and spilled the groceries. "Watch where you're going!" she snapped. "Now I've got to pick all this up!" She began to do so, then stopped and looked at him as though sizing him up. "Hold on..."

She let the apples she'd picked up fall to the ground and slowly moved her hands so that her arms were crossed. Her eyes flicked from his messy hair to his long nose and down to his shoes.

"Oh, dear," she said quietly. "I don't think that was part of the plan."

"You don't think what was part of what plan?" He was curious, now.

"You're the Doctor."

"Yep." He looked at her, frowning. "Hang on, how d'you know that?"

"The shoes give it away," she said. "No normal human being is crazy enough to wear Converse with a suit." She paused. "And you're hair's messy enough."

"That's all very well, but—how do you even know who I am?"

"I've got to go," she said suddenly, as if realizing she'd said something she wasn't supposed to. Hastily, she stuffed all the groceries back in the bags and picked them up. "Good-bye."

He ran after her as she walked quickly down the street. "Hang on!" She didn't even glance back as she turned. He came to the corner of the street and looked around.

She had most definitely come this way, but she was nowhere in sight, even on an empty and very straight street.

He sighed. This made no sense. People didn't just know who he was—he tried to keep his identity quiet. And people didn't just vanish into thin air. As much as he tried to make it work, it wouldn't.

He was still trying in vain to puzzle it out when he saw her again, the impossible girl, the girl who had absolutely no right to be here, let alone to be here looking exactly as he remembered her. She was standing there, facing away, next to the TARDIS. Her hands were against the side of the ship. He was even more sure that it was really her.

"Hello?" he said, alerting her to his presence. She whirled and pressed herself against the TARDIS, her eyes wide. She opened her mouth as if to speak, but only lowered her head. He saw she was biting her lip and she glanced up at him again, her eyes filled with some unimaginable pain. Then she spun on her heel and dashed away. He didn't bother to chase her. She was gone.

"And, she's gone again," he said. "Why did I even say anything?" He pulled out his key and stepped into the TARDIS.

Several minutes later, he heard the door open. He couldn't see it, as he was under the console, fixing things that weren't broken to begin with. "Hello?" called Leta. "Oh, you're down there. Is the TARDIS not working?"

"No, the TARDIS is fine," he called.

"What's wrong, then?"

"Nothing's wrong?"

"Come off it. You only go down there when the TARDIS is broken or when you're thinking about something. Find out anything interesting on your walk?" He saw her trainers and the cuffs of her jeans appear as she sat on the edge of the opening in the floor.

"I don't know. I would say so. Would you consider a girl who shouldn't be here and should look ten years older interesting? Or one that I've never met but she knows I'm the Doctor because of my shoes? Both of which just disappear?"

She whistled through her teeth. "Interesting sounds like an understatement."

His Chuck Taylors vanished, and a second later he climbed up out from under the console. "It is." Leta had to laugh at him, he looked so funny. He had a scowl on his face and a smear of something blue and shiny across one cheek. Not to mention all his hair sticking up at odd angles.

"So, tell me more." She kicked her feet and looked at him curiously. If there was anything she loved about traveling, it was the beyond-interesting experiences.

"Well, I was walking along the cliffs, when I saw someone I thought I knew—have I told you about Rose Tyler? No? She used to be my companion, a while ago. Sweet girl. Anyways, I thought I saw her, but then I couldn't think how that was possible, because not only should she be on Earth, a normal woman, but she should be about thirty, and she looked like she was still nineteen." He ran his fingers through his hair, which made it worse, not better. "She saw me and ran off. I chased her, but she vanished into thin air. Literally. Then I ran into this girl carrying groceries, and she looked at me and told me I wasn't part of the plan, then told me that my shoes gave me away and walked off. She vanished too."

Leta raised her eyebrows. "Just vanished? Just like that?"

"Yep. No sign of them. And the grocery girl vanished on a perfectly straight and completely empty street that she most definitely turned onto."

She grinned then. "Did you even breathe during that whole speech?"

He grinned back. "Nope."

"You should probably breathe now."

He nodded, took a deep breath, and launched straight back into his rambling. "Honestly, though, it doesn't make sense. Then I saw her again—the one I thought was Rose—standing by the TARDIS. I said hello, and she stared at me, then ran away again. I'm getting more and more confused, because if she really was Rose, why would she run away? But then, who else could look so exactly like her? And I was trying to think how she might have gotten here, and all I could come if with was that I'll go back and get her and I'll be here now with her for some reason...but if she's with me, then why was she afraid of me? Unless by then I will have regenerated." He thought about that. "But she should still recognize me. Strange, isn't that. But either way, it's no good to have two of me wandering around." He took another deep breath, beamed, and finished, "And, that's all."

Leta laughed. "So, what's the girl-who-might-or-might-not-be-Rose look like?"

"Well...like Rose. Blonde hair, a little shorter than me, uh...oh, never mind. Hang on." He ran down the hall and came back a moment later with a picture which he was careful not to look at. "Here."

She took the picture. The Doctor was standing next to a pretty girl who fit the description he'd just offered. She was laughing, the tip of her tongue showing between her teeth, swiping playfully at him as snow fell around them. He wore an orange paper crown and was grinning ear to ear. She had bits of silver tinsel in her hair.

Leta looked up at the Doctor. His face was empty, but his eyes were shadowed with the ghosts of a past she couldn't begin to imagine.

"I'm sorry," she said. He didn't answer, just looked at her. "You really miss her."

There was a pause, a few seconds of silence, before he bowed his head.

"I'll go find her," she said. "Wait here. If you wander into the middle of things, you'll ruin it."

He nodded and didn't look at her. She saluted and marched out of the TARDIS, checking first to make sure she had some money.

Leta was going grocery shopping.

A/N: Oooh. Mysteriosity. Yay!! This one, I have an idea where I'm going with. Like it? Dislike it? Review and tell me!