The Ape 1940
Plot: A kindly but disgraced doctor named Bernard Adrian is trying to find a cure for polio. His research requires human spinal fluid, but his samples are destroyed during a struggle with an escaped circus ape. Desperate to continue his work to save a young woman from paralysis, the doctor kills the ape, skins it, and uses its hide to disguise himself. He then goes on a killing spree to collect spinal fluid from his victims, with the murders being blamed on the escaped ape.
