Once upon a time, there was a little boy who believed in miracles. But that boy grew up watching as everyone and everything was taken from him. And no miracle came to save him. He grew up. Lost his faith. Lost his trust. And then… SHE arrived.

Seo's trying to make a point. And she's making it using Torchwood.

It's said that, at the Battle of Demons Run, the Doctor called in debts from all the people he'd helped, over the years. Which, after defeating the vampires, includes the Slayers. Guess what THEY were talking about?

When Seo gets a psychic distress call, she and Alison find themselves at the mercy of life-sucking aliens.