When a woman is found dead with her throat torn out, the local villagers blame a supernatural monster. But Sherlock Holmes, who gets drawn into the case from nearby Quebec, suspects a human murderer.
| Actor | Role |
|---|---|
 Basil RathboneSherlock Holmes | Sherlock Holmes |
 Nigel BruceDoctor Watson | Doctor Watson |
 Gerald HamerPotts / Tanner / Ramson | Potts / Tanner / Ramson |
 Paul CavanaghLord Penrose | Lord Penrose |
 Arthur HohlEmile Journet | Emile Journet |
 Miles ManderJudge Brisson | Judge Brisson |
 Kay HardingMarie Journet | Marie Journet |
 David ClydePolice Sergeant Thompson | Police Sergeant Thompson |
 Ian WolfeDrake | Drake |
 Victoria HorneNora | Nora |
 Al FergusonAttendant (uncredited) | Attendant (uncredited) |
 Olaf HyttenHotel Day Desk Clerk (uncredited) | Hotel Day Desk Clerk (uncredited) |
| BBobby HaleVillager in Pub (uncredited) | Villager in Pub (uncredited) |
 Harry AllenNot listed | Not listed |
 Gertrude AstorNot listed | Not listed |
 Clyde FillmoreNot listed | Not listed |
| CCharles FrancisNot listed | Not listed |
| GGeorge KirbyNot listed | Not listed |
 Pietro SossoNot listed | Not listed |