On a rainy night whilst on duty, Kang Chul-joong encounters a suspicious man in a hooded raincoat. When he tries to question him, the man cuts his face and casually walks away, leaving the weapon behind. A week later, the bodies of an old couple are found with multiple stab wounds. Investigating at the murder scene, Chul-joong recalls the man in the rain, and notices that the stab wounds on the corpses were made by the same knife. When Chul-joong comes face to face with the man he suspects is the killer, the two men attempt to outwit each other until a brutal and bloody battle to the death ensues.