To win back his soul from the Devil, a cynical witch must decide if his own freedom is worth delivering a selfless boy to damnation. Perpetually seventeen, Callum the green witch is indebted to the Devil until he fulfills 666 tasks. When Lucifer offers Callum an unusual job that will end Callum's contract early and return his soul, Callum readily agrees. All Callum must do is ensure Augustus "Auggie" Sanderson makes it from London to New York by the next blood moon. This proves more difficult than Callum could've predicted as power-hungry witch kings and queens, blood witches, and even necromancers are also out to capture Auggie. To deliver Auggie on time and win back his soul, Callum will need the help of his black cat familiar, his human assistant (whom he accidentally turned into a frog), a four-armed, tally undead witch, and Auggie himself--who seems too good to have made a deal with the Devil. But if Auggie didn't make a deal with the Devil, what awaits him in New York? And if Auggie doesn't deserve his fate, is Callum willing to give up his own chance at freedom to save him?