Lord Kensington (uncredited)

Quizmaster / Collie (voice)

Dr. Feodor Orloff

Ian Hunt

Dr. Roland Gerard

Gerry Monte aka Sabourin

Timothy Chappel

Sir Roderick Strood

Tom Martin

Tom Martin

Sir Kay

Maharajah

Tom Conway, Private Investigator

Norman Conquest

Fidel

Narrator (voice)

Roger Kingsley

Bennington

Dr. Viet

John Campbell

Christopher Adams

Whitfield Savory

Dr. Michael Madden

Capt. Hugh 'Bulldog' Drummond

Capt. Hugh 'Bulldog' Drummond

John Friday

Jefferson Van Orsdale Jr.

Dr. Robert Davis

Tom "The Falcon" Lawrence

Steve Barnes

Tom Lawrence

Lew Lentz

Tom Lawrence / The Falcon

Theodore 'Step' Allison

Tom Lawrence

Tom Lawrence, aka The Falcon

Mark Latham

Tom Lawrence / The Falcon

Tom Lawrence, the Falcon

Dr. Louis Judd

Tom Lawrence / The Falcon

Paul Holland

Tom Lawrence

Dr. Louis Judd

Tom Lawrence

Man (uncredited)

Frankie Ciro

Maurice Craindall

Louis Berex

Medford

Mr. Blanton

Mr. Channing

Morgan Pell

Captain Ferris

Edgar Wayne

Andrew Hendon

(voice) (uncredited)