Felix Castor used to cast out demons for a living, and London was his stomping ground. But in a time when the supernatural realm is in upheaval and spilling over into the mundane world of the living, his skills are in renewed demand. With old debts to pay, Castor is left with no choice but to accept one final, well-paying assignment: a seemingly simple exorcism. Trouble is, the more he discovers about the ghost in the archive, the more things refuse to add up - and the more deeply he's dragged into a world he wants no part of. What should have been a perfectly straightforward job is rapidly turning into a "who can kill Castor first" competition, with demons, were-beings, and ghosts all keen to claim the big prize. But that's okay. Castor knows how to deal with the dead. It's the living who piss him off.