In a motel is a man tied up and a woman with an axe. She is Lee Yooni, a detective that kills sex offenders at night. With her past trauma of her mother being murdered, she takes police information of sex offenders to approach and murder them. As the Special Crimes Team 3's investigation continues, Jungwon's suspicions head towards Yooni. After another murder, things start to turn unexpectedly…
