In the late Goryeo dynasty, a martial artist is murdered. His resentment causes him to be reborn as Bulgasari, an iron-eating monster, who seeks revenge on his killers.

During the later years of Goryeo Dynasty (918-1392), a talented martial artist is murdered. His resentment makes him born again as Bulgasari, a monster that grinds and eats up iron. The monster takes his revenge on the traitors responsible for his death.—Korean Film Archive