Despite being confused of his current situation, Tae Joo works hard with the detectives in 1988 to solve a murder case. Upon looking at the case, he is certain that it is a serial murder. He has a hard time accepting the way that the 1988 detectives work and gets into an argument with Dong Cheol. Tae Joo is determined to find his way back to 2018. In order to do so, he makes a dangerous decision.
한태주는 혼란스러운 와중에도 88년의 형사들과 함께 살인사건을 조사하지만, 과거 형사들의 수사 방식을 납득하지 못하고 강력반 강동철 계장과 대립하게 된다.
그리고 현재로 돌아가기 위해, 태주는 위험한 선택을 하는데..
