Konga (1961)

In Konga, an eccentric scientist named Dr. Decker experiments with hypnotism on a chimpanzee in order to enlarge it. The experiment is successful, and the chimpanzee grows into a giant ape. Dr. Decker then brings Konga to London, where it terrorizes the city and wreaks havoc. As the body count rises, it is up to a student and the police to stop the rampage and put an end to Dr. Decker's mad plans.