Reginald Owen
Dr. Watson
Alan Mowbray
Colonel Gore-King
Clive Brook
Sherlock Holmes
Brandon Hurst
Secretary to Erskine (uncredited)
C. Montague Shaw
Judge
Herbert Mundin
George
Roy D'Arcy
Manuel Lopez (uncredited)
John George
Bird Shop Thug (uncredited)
Ernest Torrence
Professor James Moriarty
Ivan F. Simpson
Faulkner
Miriam Jordan
Alice Faulkner