An artist, John Jaspers sells his soul to the mysterious "M" in order to get revenge on the people who killed his girlfriend. Soon, he realizes everything has a price, and he is transformed into a horned demon with a passion for killing. He learns that M plans to release the Homunculus, a giant Lizard-like monster onto the earth, opening the gate to hell. Now, Jaspers must stop M before he can let the apocalypse begin...