Fierce and feared Zeus gang boss Jang Dong-su (MA Dong-seok) gets involved in a fender bender on a rain night and gets attacked without warning, ending up with several severe wounds. After fighting back, he barely kept his life but his reputation as a gang boss is damaged beyond repair. His only way to somehow get his image on track is to find his attacker and exact revenge. He decides to team up with Det. Jung Tae-seok (KIM Moo-yul), who believes that Jang's attacker is none other than a serial killer.