In a small town a killer is running loose and many suspect a vampire as the bodies have been drained of blood.
The local police inspector, played by Melvyn Douglas is very skeptical of the vampire theory, but a local doctor, played by Lionel Atwill attempts to show him proof of vampirism thru books on the subject.
The locals however want to place all the blame on local crazy Herman Gleib, played by the marvelous Dwight Frye. After they kill him, the killings still continue and it is soon learned that Lionel Atwill is the mad scientist behind the murders. He is trying to feed a strange protoplasmic creature he has in an aquarium.
Lovely Fay Wray is the menaced heroine in this film and she always looks good and it's great to see her in anything.