Claire Forrest seeks her kidnapped scientist father, hidden somewhere on Mystery Island. He is held and forced to work on diabolical inventions by Captain Mephisto, a costumed villain.

When a small town doctor buries his twin brother, a practitioner of the black arts, he believes him dead; but subsequent events force him to realize that his brother has,…

James Kincaid controls the local water supply and plans to do away with the other ranchers. Government agent Sandy Saunders arrives undercover to investigate Kincaid’s land swindle scheme, and win…