Dan Warden rejoins Southern law enforcement as the chief investigator for an Alabama sheriff's department. As he hunts for an elusive serial killer who leaves baffling clues, a woman who may be clairvoyant offers to help. Dan's task becomes more difficult when Sid Landers, a raunchy, homicidal ex-con shows up with his mentally challenged half brother who likes to be called Digger.

Sid Landers spent the last ten years in a Texas prison for killing another man in a barroom fight. The prison psychiatrist told Sid that he has a type of impulse control disorder, Intermittent Explosive Disorder, which causes him to have episodes of uncontrolled aggression that are grossly out of proportion to the situation that initiated the episodes. Some of these episodes cause Sid to become a suspect in Dan's investigation for the serial killer.

As political and professional pressures mount to close the case before the killer strikes again, Dan attempts a personal agenda to reunite with his ex-wife and children.