Frederick Loren has invited five strangers to a party of a lifetime. He is offering each of them $10,000 if they can stay the night in a house. But the house is no ordinary house. This house has a reputation for murder. Frederick offers them each a gun for protection. They all arrived in a hearse and will either leave in it $10,000 richer or leave in it dead!
A college paleontology professor acquires a newly discovered specimen of a coelecanth, but while examining it, he is accidentally exposed to its blood, and finds himself periodically turning into a murderous Neanderthal man.
Teenagers from a small town and their high school science teacher join forces to battle a giant mutant spider, living in a cave nearby and getting hungry.
A man and wife are terrorized by Mad Scientist Dr. Callistratus who was executed but has returned to life with a heart transplant. Along with his crippled assistant Carl, the 'anemic' Mad Scientist, believed to be a vampire, conducts blood deficiency research on the inmates of a prison hospital for the criminally insane to sustain his return to life.
Glenn Manning, "The Amazing Colossal Man," believed dead after falling from the Hoover Dam, reemerges in rural Mexico, brain damaged, disfigured, and very angry.
A group of scientists travel to a remote island to study the effects of nuclear weapons tests, only to get stranded when their airplane mysteriously explodes. The team soon discovers that the tests have given rise to crabs mutated into intelligent, impervious, telepathic giants intent on increasing their numbers by breeding, then travelling to populated areas to feed, and which do not intend to be stopped by their discoverers.
When the first manned flight to Venus returns to Earth, the rocket crash-lands in the Mediterranean near a small Italian fishing village. The locals manage to save one of the astronauts Colonel Calder, the mission commander. A young boy also recovers what turns out to be a specimen of an alien creature. Growing at a fantastic rate, it manages to escape and eventually threatens the city of Rome.
The arrival in a small mountain town of a dissheveled stranger launches a series of murders committed by some sort of animal. As the town doctor and his daughter attempt to help the stranger, the sheriff investigates the murders; and they uncover a sinister experiment involving two rogue scientists, a car accident victim, his wife and children, and a serum that causes a man to turn into a ravaging werewolf.
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.
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.
London, 1888: on the night of the third Jack the Ripper killing, soft-spoken Mr. Slade, a research pathologist, takes lodgings with the Harleys, including a gloomy attic room for "experiments." Mrs. Harley finds Slade odd and increasingly suspects the worst; her niece Lily (star of a decidedly Parisian stage revue) finds him interesting and increasingly attractive. Is Lily in danger, or are her mother's suspicions merely a red herring?
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.
On the beach one night, Christine Faber, two years a widow, thinks she hears her late husband Paul calling out of the surf...then meets a tall dark man, Alexis, who seems to know all about such things. After more ghostly manifestations, Christine and younger sister Janet become enmeshed in the eerie artifices of Alexis; but he in turn finds himself manipulated into deeper deviltry than he had in mind...