I, the Executioner

In Japan in 1968, a teenage boy takes his own life, and the police begin looking for what led him there. Detective Kawashima (Makoto Satō) works the case in a Tai Kato crime thriller that keeps tying the boy's death to the movements of a serial killer. The more the detectives learn, the closer the case comes to the people around the boy, and someone is still out there killing.