A scientific experiment involving subjecting a corpse to an extreme charge of electricity accidentally revives an executed criminal and makes him impervious to harm, allowing him to seek revenge on his former partners, and deal similarly with anyone else who gets in his way.
A marine biologist and a government agent investigate mysterious deaths and rumors of a sea monster in a secluded ocean cove, and find themselves involved with a marine biology professor conducting secretive experiments, international spies trying to steal his secrets, a radioactive light on the sea bottom, and the malevolent thing which guards it.
After a nuclear attack, an unlikely group of survivors, including a geologist, a crook and his moll, and a prospector, find temporary shelter in the remote-valley home of a survivalist and his beautiful daughter, but soon have to deal with the spread of radioactivity - and its effects on animal life, including humans.
Dr. Eric Vornoff, with the help of his mute assistant Lobo, captures twelve men for a grisly experiment; His goal to turn them into supermen using atomic energy. Reporter Janet Lawton, fiancée of the local lieutenant, vows to investigate Vornoff's supposedly haunted house.
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.
Commando Cody, 'Sky Marshal of the Universe', works with American scientists Joan Gilbert and Ted Richards in the development of a flying suit and a rocket to the Moon. When the nation's defences are being sabotaged and destroyed, Cody learns that an atomic-gun is being used and that the men on the moon are the culprits.
It is 1865 and Union prisoners use a military balloon to escape a Southern prison camp near the end of the Civil War. The balloon drifts for days and finally lands on a mysterious volcanic island with very unusual inhabitants. Also landing, in a better aircraft, is Rulu, a visitor from Mercury. She seeks a radio-active material that will enable her to manufacture an explosive that will destroy the world or, at least, the portion known as Earth in this 15 Chapter Serial from the 1950s.
Prof. Millard pretends to be dead and helps Jeff King ferret out Vulcan, the evil traitor at the science academy. Donning his Rocket Man costume King goes from one hair raising rescue to the next in order to keep the newly invented Decimator out of the clutches of Vulcan and his minions.
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.
Dr. Paul Carruthers is frustrated because he thinks his employers, Mary Heath and Henry Morton, have cheated him out of the company's profits. He decides to get revenge by altering bats to grow twice their normal size and training them to attack when they smell a perfume of his own making. He mixes the perfume into a lotion, which he offers as a gift to Mary and Henry. When they turn up dead, a newspaper reporter decides to investigate.
The story of a century: a decades-long second World War leaves plague and anarchy, then a rational state rebuilds civilization and attempts space travel.
In a futuristic city sharply divided between the rich and the poor, the son of the city's mastermind meets a prophet who predicts the coming of a savior to mediate their differences.