A woman who had been suffering from amnesia suddenly gets her memory back. However, she finds that she's now married to a man who she doesn't think she really loves, and she keeps having visions of a young woman who she believes is out to kill her--but she can't get anyone to listen.
1986 Gyunggi Province. The body of a young woman is found brutally raped and murdered. Two months later, a series of rapes and murders commences under similar circumstances. And in a country that had never known such crimes, the dark whispers about a serial murderer grow louder. A special task force is set up in the area, with two local detectives Park Doo-Man and Jo Young-Goo joined by a detective from Seoul who requested to be assigned to the case.
20 years ago Moo-Yeom’s father was a suspect in the "Gap Dong” serial murder case. Because of the detectives’ oppressive investigation, Moo-Yeom’s father killed himself. Now, Moo-Yeom is a detective and works to capture the killer Gap Dong. The statue of limitations has expired for the serial murder case and Moo-Yeom resigns to the belief that Gap Dong is dead. New clues though for Gap Dong appears in front of Moo-Yeom and he sets out to catch him once and for all.