In the midst of World War II, Sherlock Holmes rescues the Swiss inventor of a new bomb-sight from the Gestapo and brings him to England, where he quickly falls into the clutches of the evil Professor Moriarty.

Basil Rathbone
as Sherlock Holmes

Nigel Bruce
as Doctor Watson

Lionel Atwill
as Professor Moriarty

William Post Jr.
as Dr. Franz Tobel

Kaaren Verne
as Charlotte Eberli

Dennis Hoey
as Inspector Lestrade

Holmes Herbert
as Sir Reginald

Mary Gordon
as Mrs. Hudson

Harry Cording
as Jack Brady (uncredited)

Harold De Becker
as Peg Leg (uncredited)
CinemaSerf
Though with possibly not the most authentic Germanic accent you’ll ever have heard, “Holmes” (Basil Rathbone) still manages to smuggle Swiss scientist “Tobel” (William Post Jr.) back to London where we learn that he has developed a game-changing bombsight that could turn the war in the allies favour...