Boris Karloff as Dr. Charles Gaudet

Nedda Harrigan as Madame Lucien

James Stephenson as Col. Armand Lucien

Adia Kuznetzoff as Pierre

Rolla Gourvitch as Collette

Will Stanton as Bobo

Edward Keane as Dr. Duval

Robert Warwick as Demonpre

Pedro de Cordoba as Marcal

Tom Wilson as Emil

John Harmon as Andre

Richard Bond as Georges

Earl Gunn as Leon

Sidney Bracey as Soupy

George Lloyd as Dogface

Charles Richman as Governor Beaufort

Stuart Holmes as Gustav LeBrun

Leonard Mudie as Advocate General

Egon Brecher as Debriac

Frank Reicher as President of Assize Court

James Blaine as Guard

Dick Botiller as Pilot of Escape Boat

Al Bridge as Captain of the Guards

Nat Carr as Court Clerk

Glen Cavender as Gendarme on Train

Davison Clark as Captain of Gendarmes

Neal Clisby as Jules

Harry Cording as Guard Accepting Bribe

Gino Corrado as Man Escaping Gendarmes with Debriac

Earl Dwire as Priest

Eddie Foster as Supply Clerk

Galan Galt as Guard

Sol Gorss as Guard Escorting Gaudet After Operation

Frank Hagney as Guard

John Hamilton as Captain of Second Convict Ship

Ben Hendricks Jr. as François - Sergeant of the Guards

Stanley King as Guard

Vera Lewis as Gaudet's Housekeeper

Billy McClain as Governor's Servant

Henry Otho as Guard Handcuffing Pierre

Paul Panzer as Jury Foreman

Alonzo Price as Capt. Edvard Fearreau of the First Convict Ship

Dick Rich as Guard Drugged by Gaudet

Cliff Saum as Uniformed Gendarme

Francis Sayles as Boatman Taking Madame Lucien to Mainland

Earl Smith as Daniel - Madame Lucien's Servant

Walter Soderling as Wagon Driver

Elliott Sullivan as Gate Guard

Don Turner as Guard Escorting Gaudet After Operation

Douglas Williams as Guard