In order to survive, the soul-eating water demons of the East China Sea need to devour the pure souls of boys and girls every month. While investigating a series of bizarre cases of missing children and skeletons, the Chief Operator of the Imperial City Department and the underworld warlock Mo Chen used his keen insights (such as the cold soul-eating aura left on the skeletons and traces of special space spells) to target and severely damage the activities of the demons, destroying their hunting, and leading to a crisis for the survival of the demons. The leader of the Water Demon Tribe, "Yougui", was furious and planned revenge, abducting Mo Chen's most cherished half-demon daughter, Mo Li.
