A psychopath's ruthless serial murders have left the entire nation gripped with fear and chaos. A honest and justice-seeking rookie police officer and a veteran detective with tragic past, face against the killer. After the encounter with the psychopath, their lives totally change.

Set in the constitutional monarchy in an imaginary South Korea, South Korea's Crown Prince Lee Jae Ha is forced to join the World Officers Competition, WOC, by his brother. There, he meets North Korea's strongest female devil instructor Kim Hang Ah.