BROADCASTS.com

This film is considered the best of the Charlie Chan Warner Oland series. Boris Karloff (The Mummy) stars as the menacing Gravelle who has recently escaped from The Rockland State Sanatorium and is acting the part of mephisto in the Opera 'Carnival' he is suspected of killing his wife and her lover, as usual Chan is brought in and has to work with the police and his Number One son (Keye Luke) to solve the case but is Gravelle really the killer or is there something far more sinister going on...