There are reminders here both of Sherlock Holmes and Agatha Christie, in the mystic gloom of the environment with secret corridors and caves and even hypnotic gas, which would have interested Agatha Christie, who was the expert on chemistry in crime; but here the intrigue is just as intricate and complicated as any intrigues of hers, and like in her stories, it is impossible to figure out who the murderer is, although he has time to commit a number of murders in the course of the film, which is just for about 70 minutes. Warner Baxter's cases are always interesting, since he is both a psychiatrist with a criminal past who knows how to use his knuckles while at the same time he is an expert psychologist and doctor, so you can always rely on him, even when he gets into trouble himself and starts sleepwalking finding strange dead bodies in strange places. This is criminal entertainment and almost as good as any Sherlock Holmes adventure, while you will not be the only one to be surprised at the end.
