Lee Yeon was once the mountain guardian spirit (nine tailed fox ). During many centuries he lives his life in human form in search for the reincarnation of his lost first love and eradicates supernatural beings that threaten the mortal world. Meanwhile, Nam Ji-A works for TVC station as a PD of documentaries. She seeks out stories on the supernatural. Her parents were involved in a mysterious car accident and disappeared. She remembers a man that saved her in that accident. Rang, Lee Yeon's half-human younger brother, harbors a deep-seated contempt for all people. He continuously harms human beings as a way of pestering his brother.