Konga #1

After his plane crashes in Africa, Doctor Decker is befriended by a small monkey named Konga as well as natives that stand nearly 12 feet tall. Decker discovers that the natives drink a serum concocted from seeds of a giant plant which is what causes their immense growth. Bringing Konga and some plant seeds back to England with him, Decker creates the serum and injects Konga with it. Konga grows into a gorilla and eventually into a giant that rampages through London before being destroyed by the military.