Warren Hull

as Mandrake the Magician

Doris Weston

as Betty Houston

Al Kikume

as Lothar

Rex Downing

as Tommy Houston

Edward Earle

as Dr. Andre Bennett

Forbes Murray

as Professor Houston

Kenneth MacDonald

as James Webster

Don Beddoe

as Frank Raymond

Dick Curtis

as Dorgan

John Tyrrell

as Dirk

Stanley Brown

as Green

Beatrice Curtis

as Rest Home Nurse

Robert Sterling

as Henchman

Sam Ash

as George Regan

Lester Dorr

as Gray

Ernie Adams

as Brown

Eddie Fetherston

as Rest Home Henchman

Eddie Foster

as Ed

Knox Manning

as Narrator

Ernie Alexander

as Cabbie

Harry Bernard

as Construction Camp Watchman

Stanley Blystone

as Henchman CX12

Buel Bryant

as Rest Home & Ironworks Henchman

Budd Buster

as Construction Camp Henchman

George Chesebro

as Baker

Charles Dorety

as Mill River Inn Henchman

Jerry Frank

as Harper Drive Henchman

Kit Guard

as Powerhouse Henchman

Frank Hagney

as Harris

Chuck Hamilton

as Bank Henchman

Eddie Hart

as Williams

Oscar 'Dutch' Hendrian

as Powerhouse Henchman

Jerry Jerome

as Ward

Eddie Laughton

as Kidnapping Henchman

Tom London

as Mill River Inn Henchman

Stanley Mack

as Roadster Henchman

Pat McKee

as Dam Henchman

Charles McMurphy

as Construction Foreman

Frank Mills

as Gas Station Hitman

Art Mix

as Ironworks Henchman

Eddie Parker

as Henchman

Ralph Peters

as Mohawk Steward-Henchman

Rose Plumer

as Ship Passenger

Cyril Ring

as Magic Mart Henchman

Cy Schindell

as Bank Henchman

Charles Sherlock

as Ship Henchman

Reginald Simpson

as Parsons

Tom Steele

as Powerhouse Henchman

Charles Sullivan

as Henchman-Driver

Harry Tenbrook

as Streeter

George Turner

as Apartment-Raider

Frank Wayne

as Henchman

Blackie Whiteford

as Construction Camp Henchman

Bud Wolfe

as Tower Henchman

Bert Young

as Rest Home Henchman

Steve Clark

as Henchman (uncredited)