• 
  Alfred L. Werker

  regizor

• 
  Edwin Blum

  scenarist

• 
  Basil Rathbone

  Sherlock Holmes
• 
  Nigel Bruce

  Dr. Watson
• 
  George Zucco

  Profesorul Moriarty
• 
  E.E. Clive

  Inspector Bristol
• 
  Frank Dawson

  Dawes
• 
  George Regas

  Mateo

• 
  Neil Fitzgerald

  Clerk of the Court
• 
  Charles Irwin

  Marine Sergeant [Extra]
• 
  Frank Baker

  Unconfirmed Presence [AFI Catalog Name: Tompkins]
• 
  Ivan F. Simpson

  Unconfirmed Presence [AFI Catalog Name: Gates]
• 
  Holmes Herbert

  Justice
• 
  Mary Forbes

  Lady Conyngham
• 
  Alan Marshal

  Jerrold Hunter

• 
  Arthur Hohl

  Bassick
• 
  Brandon Hurst

  Unconfirmed Presence [AFI Catalog name: Footman]
• 
  Henry Stephenson

  Sir Ronald Ramsgate
• 
  Harry Cording

  Second Phoney Policeman [Extra]
• 
  Mary Gordon

  Mrs. Hudson
• 
  Eric Wilton

  Conyngham Butler
• 
  Leyland Hodgson

  Unspecified Bobby
• 
  Ida Lupino

  Ann Brandon
• 
  Frank Benson

  Unconfirmed Presence [AFI Catalog Name: Cockney]
• 
  Terry Kilburn

  Billy
• 
  May Beatty

  Mrs. Jameson
• 
  Peter Willes

  Lloyd Brandon

• 
  William Gillette

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