Former ghostbuster Felix "Fix" Castor is once again spirited into a case which it's in his own best interests to avoid. The sign on his door now reads Spiritual Services, which he renders rather than performing exorcisms as he once did. Fix is drawn into this case by the widow at the funeral of a former colleague, John Gittings. John, an easy-going guy in life, has become a violent spirit ("gone geist"), and is terrorizing the love of his life. Apparently, she's not the love of his afterlife.
There is, of course, far more to the case than a mere restless spirit. As he investigates--with the assistance of long-suffering cop friend Gary Coldwood and non-practicing succubus Juliet Salazar--he discovers an underworld (in both senses of the word) resurrection ring, involving mobsters, lawyers, and at least one American serial killer.