Atomic scientist/pilot Doug Martin is missing after his plane crashes on an reconnaissance mission after a nuclear test. Miraculously appearing unhurt at the base later, he is given sodium amethol, but authorities are skeptical of his story that he was captured by aliens determined to conquer the Earth with giant monsters and insects. Martin vows to use existing technology to destroy them.
A scientist develops a formula which will cause animals to regress to the form of their primitive ancestors, and tries it on himself with disastrous results.
A mad scientist, Dr. Aranya (Jackie Coogan), has created giant spiders in his Mexican lab in Zarpa Mesa to create a race of superwomen by injecting spiders with human pituitary growth hormones. Women develop miraculous regenerative powers, but men mutate into disfigured dwarves. Spiders grow to human size and intelligence.
The Singer Duke Mitchell meets Sammy Petrillo in this parody of Martin & Lewis. They arrive on a jungle island, where a mad scientist played by Bela Lugosi makes human experiments.
The unassuming, nebbishy inventor Sidney Stratton creates a miraculous fabric that will never be dirty or worn out. Clearly he can make a fortune selling clothes made of the material, but may cause a crisis in the process. After all, once someone buys one of his suits they won't ever have to fix them or buy another one, and the clothing industry will collapse overnight. Nevertheless, Sidney is determined to put his invention on the market, forcing the clothing factory bigwigs to resort to more desperate measures...
The film's storyline involves five survivors, one woman and four men, of an atomic bomb disaster. The five come together at a remote, isolated hillside house, where they try to figure out how to survive.
Claire Forrest seeks her kidnapped scientist father, hidden somewhere on Mystery Island. He is held and forced to work on diabolical inventions by Captain Mephisto, a costumed villain.
Superman has to thwart wartime saboteurs tampering with things at the Metropolis Munitions Plant...who have captured Lois Lane and loaded her into a torpedo!