Due to his heart being swapped with Gwi-Ho's, Hyeon-Ryeong exists in a realm between the living and the dead. But when his village is plagued by a series of enigmatic killings, a formidable shaman-girl named Gab-Jin appears. As Hyeon-Ryeong's transformation into a demon accelerates, he embarks on a quest with Gab-Jin to locate Gwi-Ho and restore his humanity.