Magician Leopold Kazsmer, the great enchanter, and his cadre of unusual friends, make the deadly journey to the Library of the Damned, a structure fluctuating between the worlds, filled with the archives of the centuries, to find a way to rescue Leopold’s father who is trapped in the darkest depths of Gehenna and to break the covenant Leo has made with the dread Unholy Hosts. They have suddenly called upon him to fulfill their agreement, and because he is bound to them, he has no hope but to obey. It seems that what they most desire is to destroy Leopold’s world. If he can’t stop them, he might be trapped himself in the depths of Gehenna for all eternity. With the help of the Special Inspector Mingli Zhao, the imp Suchah, the ghost of Inspector Despenser Thacker, the automaton Raj, and led by Leopold's daemon friend Eurynomos, Gehenna goes to war with England, and all hell literally breaks loose in this final adventure of the Enchanter Chronicles.