When the mutilated, acid-burned body of a teenage girl falls from a car's trunk a serial killer called 'Doc Holiday' is the prime suspect. This sadistic murderer has already taken eight lives in a ritualistic fashion and police fear the teen may be his ninth victim. Detectives Sam Kovac and Nikki Liska investigate the murder of the unidentified girl - dubbed 'Zombie Doe' by the media.
Turns out 'Zombie Doe' is Penelope Gray, a high school classmate of Liska's son Kyle. Talking to students reveals that 'Gray' (as her friends call her) was at a teen hangout the night she disappeared, as was Kyle and a number of other students - some of whom were bullies who tormented both Gray and Kyle. Questioning Gray's mother and her fiance reveal that Gray was a troubled teen, angry about her parent's divorce several years before, who was prone to acting act and staying away from home.
The homicide detectives pursue evidence on the assumption that Doc Holiday killed Gray, wanting to stop him before he claims another victim. The book intersperses some first person scenes of Doc Holiday planning/committing his crimes with the story of the detectives' investigation. Liska's problems raising two sons as a single mother - one of whom is a witness in the case - also plays a part in the story.
The characters are realistically depicted, the police investigation proceeds at a good pace, and the ending is almost satisfying. All in all an okay mystery book.