Jesse Madding finds himself caught between three gorgeous men, an ancient demon, and a dedicated group of cultists ... A simple case for Gideon Keel and Jesse Madding turns into something far more complicated when they discover their friend's trouble-prone nephew was doing a lot more than just studying demon history. Jonah stole a holy book, and now the cultists he stole it from want it back. Protecting Jonah becomes even more vital when Jesse learns just who it is the cultists worship -- Castelain, an immortal demon who walks between worlds. Jesse finally has a name for the creature that stole Black John's power, the creature that wiped Gideon's memory, and the creature that possessed Emma. Might he also have a name for the being that nearly took his life and kidnapped Emma?