In preparation for sending a manned rocket into space, American scientists Dr. Quent Brady and Dan Morgan are put in charge of a program that sends various animals and insects into space to test their survival rates. After one of their rockets carrying wasps malfunctions and goes off course, a computer calculates that the rocket is likely to land somewhere off the coast of Africa. Some time later, in a remote part of Africa, Dr. Lorentz and his daughter Lorna perform an autopsy on a native and determine that he died of paralysis of the nerve centers caused by an injection of a massive amount of venom. Arobi, Lorentz's African assistant, then informs him that a monster is believed to be terrorizing people and animals in an area known as Green Hell.