Dr. Kay Scarpetta is still shocked by the tragic loss of Benton Wesley. She is trying to carry on, but she gets a letter from Benton, written before his death and left to Senator Lord, who had agreed to deliver it a year after his death.
Dr Scarpetta and Marino start working on a new case after a body is found in a container arriving from Belgium. There is writing in the container that says "Bon voyage, le loup-garou" (Have a nice trip, the werewolf). The body has a strange tattoo and wears rich clothes and there are some baby-like hairs inside the garments. Kay and Marino get in touch with European Interpol and with Jay Talley, who calls them and makes them fly to Paris to meet the Chief Medical Examiner. They get to know that the body found in the container is a member of one of the richest and oldest families of Paris, the Chandonnes, who live in an ancient mansion on theÎle St Louis. It is also rumored that this family has got a son with a rare disease that makes hair grow on his entire body (hypertrichosis). This person has always been hidden, and he is believed to have committed several murders. Kay and Jay have a short liaison, and it seems the man is really involved, while Dr Scarpetta tries to keep him at distance. Kay finds out that Lucy is in part involved in this case, since she is investigating a Miami group of weapons and drugs smugglers related to the Chandonnes, the "One Sixty-Fivers".
Back to Richmond, Virginia, Kay and Marino deal with the case of a woman brutalized and killed in a little shop and with attempts from a member of Dr. Scarpetta's team to sabotage her. Thanks to Marino, they learn that the new police chief, Diane Bray, is behind the sabotage because she wants to get control on how investigations and exams are held. Bray is also behind a drugs-smuggling operation, but she is killed with the same modus operandi as the young woman in the shop. It is clear that the killer is at large and trying to kill the people investigating the death of the man in the container.
Dr Scarpetta is in her house when the alarm rings. The police come quickly, but they find nothing. After a while, someone knocks at her door claiming to be a police officer and that someone had reported seeing a prowler. Kay does not realize that le loup garou is fluent in English, and she opens the door. She then realizes that she is under attack. During the struggle, Kay throws a bottle of formalin onto the loup garou's face, which temporarily blinds him.
She then runs out of the house, but falls and fractures her elbow, making her unable to fire her gun. At this time, Lucy and Jo return, and Lucy runs over and points a gun at the assailant's head, with the intention of killing him, but Marino and Kay convince her not to do it.