After her parents were killed, Katie left Boston to live with Grandma Cleaves in London. It still seems like a bad dream. But she's doing okay, even making new friends.

A bit of a history buff, Katie likes living in a city where so much has happened, likes walking the same streets as the authors of Dracula and the Sherlock Holmes mysteries. This cool, bookish teen is working on her British accent and even learning some Cockney rhyming slang from handsome Toby.

When a museum visit with friends turns funky, Katie finds herself in a long, uncomfortable dress, wearing a ridiculous hat. What happened to her jeans and high-top sneakers? Where's her iPhone? It's London, 1888. Smart, gutsy Katie realizes she's here to stop a serial killer. She can't bring her parents back, but maybe she can save these women. Katie 's read about the Ripper, knows the names of his victims, even knows where and when they were killed. She's watched her fair share of CSI, knows about profiling and forensics. Surely she knows enough to save the lives of his victims. But how will changing history affect the lives of those she loves most?