For over 400 years, the world has been a barren wasteland. The few humans that survive scrape together an existence in the cruel city of Pocatel--or go it alone in the wilderness beyond, filled with wandering spirits and wyrms. They don't last long. 13 year-old pickpocket Leandro and his sister Gabi do what they can to forge a life in Pocatel. The city does not take kindly to Cascabeles like them--the descendants of those who worked the San Joaquin...

When their parents, two temporal researchers who travel through time to document history, are transferred to 17th-century Prague, Dawk and Hype hardly expect to find themselves in the middle of an alchemical mystery. In fact, the new, boring job is meant to be a punishment for Dawk and Hype's bad behavior at their last temporal post. The teenagers are from the 25th century--how could medieval Prague compare? But when they meet a man who claims he...