Meanwhile, back in the past

"I don't like these clothes," said future Rose Tyler as she tugged at the collar of her black dress and walked down the street toward a local church. "They're too stuffy."

"Well, I can't let you go naked like you normally do, Rose," said the woman who was accompanying her --- a woman who used to be Marcie Ross. "Your Mistress would not allow it."

"Clara is my Mistress," said future Rose. "She would totally allow it."

"Of course she is," said Marcie. "But she isn't here right now. I'm here. And anyway, your Mistress demanded that I put you in those clothes so that the two of us could blend in. We don't need to be attracting any more attention than we have to."

"So how come we're both carrying crossbows?" asked future Rose.

"The same reason I have a stake tucked in my garter," said Marcie. "In case we're attacked."

"Who would attack us on a nice day like today?" asked future Rose.

"You know who, Rose," said Marcie. "The two people your Mistress warned us about."

"Clara is my Mistress," said future Rose. "She didn't warn me about anybody."

"Okay, then," said Marcie. "The tall brooding male vampire and the blonde female vampire."

"Vampires?" asked future Rose. "Are you sure they exist?"

"Yes, I'm sure," said Marcie. "Quite sure."

"I helped the Doctor fight a group of aliens once," said future Rose.

"That's nice," said Marcie.

"They acted like vampires but they really weren't," said future Rose. "They were aliens."

"Okay," said Marcie.

"I know you're only humoring me, Marcie -- er, I mean, Cordelia -- but they really did exist," said future Rose. "Of course I wore clothes back then. And that time seemed so long ago."

"You're wearing clothes now," said Marcie.

"Yes," said future Rose. "But these were different clothes. I didn't have to wear a corset with these clothes. I'm beginning to feel like Keira Knightley in that movie."

"What movie?" asked Marcie.

"That movie where she complains about wearing a corset," said future Rose.

Then future Rose stopped and stared ahead at something.

"I didn't think she'd be here," said future Rose.

And then suddenly future Rose lifted up her skirts and started running ahead -- or at least she ran as fast as her clothes would let her.

"Wait, Rose!" cried Marcie. "Wait!"

But future Rose apparently did not hear her for she never stopped running.

And then Marcie saw what future Rose had seen and thought, Oh, no!

And then she lifted up her skirts and starting running too.