The Invisible Monster

Richard Webb

— Lane Carson

Aline Towne

— Carol Richards

Stanley Price

— The Phantom Ruler

Lane Bradford

— Burton

John Crawford

— Harris

George Meeker

— "Harry Long"

Edward Keane

— Warren Madison

Dale Van Sickel

— Otto Wagner, aka "Frank Martin"

Douglas Evans

— "James Hunter"

John Hamilton

— "Henry Miller"

Roy Gordon

— Mr. Moore

Harold Goodwin

— Kirk - Body-Shop Henchman [Ch.11] (uncredited)

Marshall Reed

— Roadblock Cop [Ch. 1, 7]

David Sharpe

— Garage Watchman [Ch. 3] / Armored Car Guard [Ch. 11]

George Magrill

— Henchman Sam [Ch. 4-5]

Guy Teague

— Decoy & Dumptruck Henchman [Ch. 5, 7]

Tom Steele

— Henchman Bill 'Mack' Haines [Chapters 5, 10]

Eddie Parker

— Barn Henchman Stoner [Ch.8]

Keith Richards

— Doctor [Ch. 12]

Duke Taylor

— Second Roadblock Cop [Ch. 1 bit]

Mark Strong

— Bank Watchman [Ch.1 bit]

Bert LeBaron

— Crooked Watchman [Ch. 2 bit]

Frank O'Connor

— Chemical Truck Cop [Ch. 5 bit]

Forrest Burns

— Watchman Joe [Ch. 5 bit]

Carey Loftin

— Dynamite Henchman Dirk [Ch. 6 bit]

Tom Monroe

— Cave Policeman [Ch. 7 bit]

Howard M. Mitchell

— Second Garage Watchman [Ch. 7 bit]

Charles Sullivan

— Squadcar Cop [Ch. 7 bit]

George Volk

— Second Armored Car Guard [Ch. 11 bit]