Don Cesar De Vega crosses swords with a vicious member of the Queen's Guard, and steals the affection of a young heiress. When the officer frames the young upstart for murder, Don Cesar fakes his own death and retreats to the crumbling ruins of the family castle he plots his vengeance.

Daniel Boone Brown is a pleasure-seeking playboy carousing around New York City without a care in the world -- that is, until he becomes the unwitting subject of a series of experiments at the hands of a sadistic psychiatrist.