After a year spent in 'retirement' Castor is reluctantly drawn back to the life he rejected and accepts a seemingly simple exorcism case - just to pay the bills, you understand. Trouble is, the more he discovers about the ghost haunting the archive, the more things don't add up. What should have been a perfectly straightforward exorcism is rapidly turning into the Who Can Kill Castor First Show, with demons, were-beings and ghosts all keen to claim the big prize.
But that's OK; Castor knows how to deal with the dead. It's the living who piss him off . . .