The famous Borgia Pearl, a valuable gem with a history of bringing murder and misfortune to its owner since the days of the Borgias, is brought to London, thanks in part to Sherlock Holmes. But before long the jewel is stolen, due to an error on Holmes' part, and shortly thereafter, a series of horrible murders begin, the murderer leaving his victims with their spines snapped and surrounded by a mass of smashed china.
Basil Rathbone
as Sherlock Holmes
Nigel Bruce
as Dr. John Watson
Dennis Hoey
as Inspector Lestrade
Evelyn Ankers
as Naomi Drake
Miles Mander
as Giles Conover
Ian Wolfe
as Amos Hodder
Charles Francis
as Francis Digby, curator
Holmes Herbert
as James Goodram, courier
Richard Aherne
as Museum Guard Bates
Mary Gordon
as Mrs. Hudson
Rondo Hatton
as The Hoxton Creeper
Harry Cording
as George Gelder (uncredited)
