Mike Sweeney has been promoted to a new position as Homicide Detective. His family has been split by serial killer Ray Prager, who is in lockdown after killing two women and traumatizing (possibly raped) Mike's daughter, Sadie. Meanwhile, at work, Mike is assigned a case of a possible homicide of a baby and takes it to forensic psychiatrist, Pen Verrity to help him understand how the murder happened.

Detective Sweeney comes under suspicion of police brutality. Meanwhile a new case keeps him busy while he struggles to help Sadie prepare for the coming trial.

Mike and Tom take a closer look into Bonnie Verrity's death against Roxy's orders. Meanwhile Pen and Jonathan Verrity's fight over custody of Mark comes to a head.

New revelations into Bonnie's death are made as the investigation continues and both parents become suspects. Mike tries to stay professional while Pen draws him deeper into her web, and begins to behaves erratically and dangerously.

With three murder investigations on his plate, and his family in turmoil, Mike attempts to keep his head about him.

Things come to a head for everyone in Durham County.