Shakma

Sam (Atkins) is a medical student performing an experiment on Shakma, a baboon, at a medical school run by Professor Sorenson (McDowall). His experimental drug is supposed to make the creature less aggressive, but it ends up having the opposite effect and Sam must euthanize the animal. Sorenson wants to perform an autopsy, so orders Sam not to cremate the animal. Sam, fond of the beast, merely sedates him. In doing so, Sam injects the wrong drug into him. Afterwards Shakma remains alive, and highly aggressive, unbeknownst to all.