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.
Moo Yeom is a detective. 20 years ago, he was a Buddhist monk, but he got into trouble with a man named Gap Dong. To cut ties with him and cut off whatever karma would arise from his involvement with Gap Dong, Moo Yeom became a detective. After the statute of limitations expired, Gap Dong appears once again. Moo Yeom sets out to catch him once and for all.