In a single thirty-day period, to be exact. The pace of the killings is virtually unprecedented, and if the victims were women, the city would be gripped by terror. But because the victims are middle-aged or older men, a sort of fascinated curiosity has taken hold of New Orleans. Each victim has been shot in or near the spine, mutilated with human bites, then finished off with a coup de grâce shot to the head. The bites have increased in savagery from victim to victim, and they’ve also provided the strongest evidence against any future suspect-mitochondrial DNA from the killer’s saliva.

The bite marks are the reason for my involvement with the case. I’m a forensic odontologist, an expert on human teeth and the damage they can do. I acquired this knowledge in four boring years of dental school and five fascinating years of fieldwork. If people ask me what I do for a living, I tell them I’m a dentist, which is true enough and all they need to know. Odontologist doesn’t mean anything to anybody, but in post- CSI America, forensic prompts questions I’d just as soon not answer in a grocery store. So, while most acquaintances know me as a dentist who’s too busy to accept new patients, an assortment of government agencies-including the FBI and the United Nations Commission for the Investigation of War Crimes-knows me as one of the leading forensic odontologists in the world. Which is nice. I take my identity where I can find it.

The task force wants my expertise on bite marks tonight, but Sean Regan wants more. When he sought my help on a murder case two years ago, he soon learned that I knew about a lot more than teeth. I completed two years of medical school before I withdrew, and that gave me a strong foundation for self-education in forensics. Anatomy, hematology, histology, biochemistry, whatever a case requires. I can glean twice as much information from an autopsy report as any detective, and twice as fast. After Sean and I became closer than the rules allowed, he began using me unofficially to help with difficult cases. And used is the proper word; Sean Regan lives to catch killers, and he’ll exploit anything and anyone to help him do it.