After his adventures in The Tower of Fools and Warriors of God, Reynevan is on the run again, harried by enemies--some human, and some mystical--at every turn. These are cruel and dangerous times for a man such as Reynevan, and to survive, he must set aside his history as a peaceful healer and idealist and play the brutal role of Hussite spy as crusades sweep through Silesia and the Czech Republic, and the world around him is forever changed.

Thirteenth-century Bohemia is a dangerous place for a girl, especially one as odd as Mouse, born with unnatural senses and an uncanny intellect. Some call her a witch. Others call her an angel. Even Mouse doesn't know who -- or what -- she is. But she means to find out. When young King Ottakar shows up at the Abbey wounded by a traitor's arrow, Mouse breaks church law to save him and then agrees to accompany him back to Prague as his personal healer....