The Ape brings together two legends of horror, Frankenstein star Boris Karloff and The Wolf Man writer Curt Siodmak. Karloff stars as Dr. Adrian, a man who becomes obsessed with curing paralysis when he loses his beloved wife and daughter to the disease.Desperately trying to cure a crippled neighbor (Maris Wrixon), he discovers that he needs human spinal fluid for his vaccine - but how to get it? When an ape trainer at a local circus is badly mauled, the doctor allows him to die so that he can tap his spine. The gorilla escapes and goes on a killing spree terrorizing the small town. A cult horror classic, The Ape was Karloff's final film for Monogram.