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]