British botanist Dr. Charles Decker (Michael Gough) comes back from Africa after a year, presumed dead. During that year, he came across a way of growing plants and animals to an enormous size. He brings back a baby chimpanzee, Konga, to test out his theory. Decker goes insane after he discovers a serum that turns his chimpanzee subject into a ferocious gorilla-sized ape. To further his hideous experiments, he mesmerizes the chimp and sends it to London to kill all his enemies who want more credit in the scientific community than he already has. Among his targets is Dean Foster (Austin Trevor) Professor Tagore (George Pastell) and Bob Kenton (Jess Conrad), the lover of Sandra Banks (Claire Gordon), the woman the doctor wants for himself.
After Konga strangles Bob Kenton to death, Dr. Charles Decker attempts to make Sandra Banks his own. This doesn't sit well with Margaret (Margo Johns), the botanist's assistant and current girlfriend, who attempts to get even by giving Konga an enormous amount of the strange serum and turns him into an enormous monster, although she becomes his first victim.
Just before going on a rampage, the super-sized ape grabs Dr. Charles Decker in one of his enormous hands, while Sandra's Banks arm is eaten by Dr. Charles Decker's carnivorous plants. His rampage comes to a stop when he and Dr. Charles Decker are killed by the British army. Upon his death, Konga reverts to a chimpanzee.
What kind of scientist is Dr. Charles Decker?
botanist