as

Eddie Carter

as

Daubeney Carshott

as

John Ainsworth

as

Dr. Steven Russell

as

Dr. Craig Mitchell

as

Doctor Marshall

as

Dr. Marshall, 'The Scorpion'

as

Capt. Jerry Brown / Jim Lofton

as

Frank Gordon

as

Owen Rogers

as

Curtis Powell

as

Agent Ted Kelly

as

Bruce Donaldson

as

Lieut. Dan Burke

as

Henry Townsend

as

Capt. John Kent

as

Graham Smith

as

Attorney Johnson

as

Ted 'Rip-Roaring' Riley

as

Andrew Robinson

as

Robert Thornton

as

Jimmy Milligan

as

Daniel Treve

as

Bill Ramsey

as

Prince Nicholas Petroff

as

Bart Wallace

as

Dr. Robert Sanford

as

Tony Hill

as

Fred Garlan

as

Derek

as

Johnny Stark

as

Jack

as

Bill

as

George Edward Blaine

as

Marshall Jones

as

Nikolai Roget

as

Bobby Bailey

as

Dr. Bradford

as

Don Manning

as

Philip Lennox

as

Cal

as

Hayden Eaton

as

Jerry Booth

as

Franz Pless

as

Jerry

as

John Barton

as

Donald Marshall

as

Waite Lifter

as

Gil Barry

as

Felipe

as

Theodore Wayne

as

Julian Perryam

as

Richard Castleman / Danny Rowland

as

Edward E. Malone

as

Charlie Jordan

as

Ned Thayer

as

Philip Collett

as

Blair Farquar

as

Rance Conway

as

Phil Douglas

as

Lionel Tressilian

as

John Trevor

as

Jack Hare

as

Dick Forrest

as

The Hero

as

Sam Gladding

as

Oliver Wendell Blaine

as

Cody Jacques

as

Harvey Livermore

as

Frederick Graves

as

David Beresford

as

John Trott

as

Dick Revel

as

Luther Flint

as

Himself

as

Roger Moran

as

Roland

as

John King

as

Tad Worden

as

Jules Patricia

as

Reporter (uncredited)