A prophecy names Pacifica Casull the poison that will destroy the world on her sixteenth birthday, and the church of Mauser has hunted her since she was an infant. She crosses the countryside with her adoptive siblings, the swordsman Shannon and the sorceress Raquel, who turn away the assassins, bounty hunters and knights sent after her. What starts as a chase across a fantasy kingdom begins turning up where the prophecy actually came from.