Sa Hyunwoo works at the “Healing Agency,” where he takes down evil spirits and exorcises possessions with nothing but his bare fists—for a price. During one of his assignments, he discovers a group of villains artificially infusing evil spirits into the world, plunging it into chaos. Enraged by their tyranny that destroys everything precious to him, Sa Hyunwoo embarks on a life-or-death struggle to root out the source of evil.