4th in the Preternatural Investigation Agency series. When a werewolf is found dead in the woods, Agent Charlie Jacobs is called in by the police to assist with the investigation. After Charlie discovers that a second pack has moved into the woods on the outskirts of Riverside, he realizes that things are even more complicated than he first thought. Wolves are territorial by nature and werewolves are no exception. As more attacks happen, Charlie knows he needs to find out who is responsible before a pack war erupts. Meanwhile, as Agent Rick Thornton continues to struggle with his empathy, he encounters a terrified woman on the street and finds himself drawn into her case. It soon becomes clear that they are not dealing with an average stalker. With the help of the rest of the PIA, Rick races to stop the madman before he destroys any more minds in his search for sanity.