Spring, 1987.Sung-Jin (Son Hyun-Joo) is an enthusiastic detective with a wife (Ra Mi-Ran) and a son. His dream is to live with his family in a 2 story home. One day, he happens to catch Tae-Sung (Jo Dal-Hwan). He is a suspected serial killer and the first suspected serial killer in South Korea. Due to this incident, Sung-Jin gets involved in a secret operation led by NSP Chief Kyoo-Nam (Jang Hyuk). Meanwhile, newspaper reporter Jae-Jin (Kim Sang-Ho) senses something suspicious about Tae-Sung’s case. He recommends that Sung-Jin be removed from the case, but Sung-Jin has no choice but to get involved in the secret operation. He needs money for his son’s operation.