Prosecutor Do Ji Han firmly believes that the killer is the same killer from 30 years ago, and therefore, is a serial killer. Realizing the graveness of the situa-tion, a new team is formed solely for this case, and Pyo Yoo Seong takes the lead. Although Sol repeatedly tells Ji Han that they cannot ignore the possibility of a copycat, Ji Han refuses to listen.
30년 전 온 국민을 떨게 한 연쇄살인범이 다시 움직이기 시작하고, 범인을 잡기 위해 국과수와 동부지검의 합동수사본부가 꾸려지는데..