This is the twelfth book in the Anita Blake series. Anita is finally getting a handle on the Ardour, when she accidentally manages to form a second triumvirate with Nathanial and Damian. The new triumvirate seems to have sent all triumvirate members, from both triumvirates, to a new level of power, and no one is quite sure what all the new powers are. Also, Nathanial is not happy with things the way they have been, and now Anita has to figure out what to do.
Also there is a serial killer loose in town, a vampire one, that seems to be a Master not tied to Jean Claude or Malcolm, the leader of the vampire church. Anita needs to find the killer, and figure out what to do with her personal life.