Sherlock Holmes

Basil Rathbone

Acting

Doctor Watson

Nigel Bruce

Acting

Nancy Partridge

Marjorie Lord

Acting

William Easter

Henry Daniell

Acting

Heinrich Hinckel aka Richard Stanley

George Zucco

Acting

Naval Lt. Pete Merriam

John Archer

Acting

Mr. Lang, government agent

Gavin Muir

Acting

Detective Lt. Grogan

Edmund MacDonald

Acting

Howe

Don Terry

Acting

Mrs. Hudson

Mary Gordon

Acting

Cady

Bradley Page

Acting

George

Clarence Muse

Acting

Mrs. Pettibone

Mary Forbes

Acting

Mr. Ahrens

Holmes Herbert

Acting

Sen. Henry Babcock

Thurston Hall

Acting

Antiques Store Sales Clerk

Ian Wolfe

Acting

Army Inspector (uncredited)

John Burton

Acting

Alfred Pettibone

Gerald Hamer

Acting

Sir Henry Marchmont (uncredited)

Gilbert Emery

Acting

Miss Pringle (uncredited)

Margaret Seddon

Acting

Party Pianist (uncredited)

Mary Field

Acting

Hotel Doorman (uncredited)

Colin Kenny

Acting

Mrs. Ruxton

Caroline Frances Cooke

Acting