After five years of working for the Devil, Claire Cooper believes she lives an otherwise normal life. Until she finds herself in jeopardy for a murder she did not commit. Desperate to save her life and soul, she enters Purgatory, but runs afoul of the Devil's sister, Pagan Queen Mab. Mab has her own agenda and uses Claire to get even with the Devil. Claire learns each ruler is in a race to discover “the girl” in the prophecy to fix time. As Claire peels away clues to the real killer, she realizes she must outwit the Devil’s children or end up a prisoner in Purgatory forever.