Sixteen-year-old Gwyneth discovers that she, rather than her well-prepared cousin, carries a time-travel gene, and soon she is journeying with Gideon, who shares the gift, through historical London trying to discover whom they can trust.

When a terrifying encounter in London reveals that one of her most-trusted allies is actually a rogue double-agent, Cammie Morgan no longer knows if she can trust her classmates, her teachers--or even her own heart.

Jonathan Starling's father is in an asylum and his home has been attacked when, while running away from kidnappers, he stumbles upon Darkside, a terrifying and hidden part of London ruled by the descendents of Jack the Ripper, where Jonathan is in mortal danger if he cannot find the way out.