A convicted thief in Dartmoor prison hides the location of the stolen Bank of England printing plates inside three music boxes. When the innocent purchasers of the boxes start to be murdered, Holmes and Watson investigate.
as Sherlock Holmes
as Dr. John H. Watson
as Mrs. Hilda Courtney
as Colonel Cavanaugh
as Hamid
as Inspector Hopkins
as Ebenezer Crabtree
as Julian 'Stinky' Emery
as Evelyn Clifford
as Mrs. Hudson
as Commissioner of Scotland Yard
as Tour Guide
as Antique Shop Assistant (uncredited)
as Detective at Murder Scene
as Photographer
as Joe Cisto
as Pub Patron (uncredited)
as Convict at Dartmoor Prison (uncredited)
as Cab Driver (uncredited)
as Alfred - Auction House Bookkeeper (uncredited)
as Pub Patron (uncredited)
as Minister's Wife (uncredited)
as Pub Patron (uncredited)
as Crabtree's Assistant at Auction (uncredited)
