A series of murders holds the nation in its sway and the longer the police fail to catch the murderer, the more the public begins to panic. Choi, a highly successful investigator whose methods have always held him back from promotion, senses that this case might be his last chance to make something of his career. He and his old mentor Jang agree to arrest the next best suspect as the serial killer – whatever it might cost. Just when it looks as if all the dirty tricks, dark deeds and treacherous secret deals are about to be exposed, all the stakeholders find themselves drawn deeper into the morass of questionable morals and open violation of the law. The search for the murderer begins to unite the four men, even though none are particularly interested in finding the culprit.