Mysterious Doctor Satan

Eduardo Ciannelli

Doctor Satan

Robert Wilcox

Bob Wayne / Copperhead

William Newell

Speed Martin

C. Montague Shaw

Prof. Thomas Scott

Ella Neal

Lois Scott

Dorothy Herbert

Alice Brent

Charles Trowbridge

Gov. Bronson

Jack Mulhall

Police Chief Rand

Edwin Stanley

Col. Bevans

Walter McGrail

Stoner

Joe McGuinn

Gort

Bud Geary

Hallett

Paul Marion

Corbay

Archie Twitchell

Ross

Lynton Brent

Scarlett

Ken Terrell

Corwin

Al Taylor

Joe

George Allen

Henchman-Driver Spike (uncredited)

John Bagni

Gray, Pick-up Thug

Frank Brownlee

Panamint Pete

James Bush

Co-Pilot

Yakima Canutt

Sailor at Winch

Virginia Carroll

Nurse

Ed Cassidy

Barton

Davison Clark

Police Lieutenant

Tristram Coffin

Wells - Governor's Secretary

Frank Conklin

Station Master Burns

Fred Criswell

Officer

Eddie Dew

Gas Station Attendant

Frank Ellis

Plant Henchman

James Fawcett

Al

Sam Garrett

Roper

Duke Green

Duke - Mine Thug

Alan Gregg

Red - Mine Thug

Kenneth Harlan

Capt. Lathrop

Charles Hutchison

Proprietor

Jerry Jerome

House Heavy

Patrick Kelly

Plant Henchman

Marten Lamont

Steve - Pilot

Bert LeBaron

Henchman Fallon

Jack O'Shea

House Heavy

Eddie Parker

Chuck - Lead Truck Thug

Hal Price

P&G Warehouse Mgr.

Ernest Sarracino

Henchman-Guard

Cy Schindell

Jake - Biplane Pilot

William Stahl

Detective Brock

Ted Stanhope

Warehouse Watchman

Tom Steele

Truck Henchman

Harry Strang

Police Officer Davis

Duke Taylor

Watkins - Fire Escape Thug

Robert Wayne

Detective Perry

Wally West

Palmer - Thug

Lloyd Whitlock

Prof. Williams

Bill Wilkus

Truck Henchman

Bud Wolfe

Sailor at Cable