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.

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Main Cast: Richard Bailey, Linda Stirling, Roy Barcroft, Kenne Duncan, Forrest Taylor, Forbes Murray, Jack Ingram, Harry Strang, Ed Cassidy, Frank Alten

Directors: Wallace Grissell, Spencer Gordon Bennet, Yakima Canutt

Writers: Joseph F. Poland, Jesse Duffy, Basil Dickey, Albert DeMond, Alan James, Grant Nelson

Editors: Harold Minter, Cliff Bell Sr.

Cinematographer: Bud Thackery

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