A five-year-old child was murdered in such a hideous way, and the Special Crime Squad is having a hard time because they don't have a suspect. Meanwhile, Ha Young and Young Soo go on the first interview of an inmate together, and he happens to be a mutilation murderer. Since Ha Young is confident with his analysis, he wants to help the Special Crime Squad but, Tae Gu finds them unreliable just like everybody else.