Four exorcists, each driven by a cause of their own, join forces against the demons that rule humanity's spiritual and emotional worlds and push society toward chaos. Hyeon-Am trains in Tai Chi Qigong to fight the water ghost that killed his sister. Father Park, a doctor turned priest, chose an ascetic path after he could not save a friend's daughter from an unknown evil spirit, and his church later excommunicated him for performing exorcisms. Jun-Hu, the sole survivor of Eastern Sea Esoteric Buddhism, is a prodigy who inherited the magic of its five guardians. Seung-Hui, who hides a secret, is drawn into a mysterious case because of her father. Together they solve crimes and battle evil in an occult action fantasy film.