Two escaped convicts are found hiding in a rocketship built by a renegade inventor, who forces them to become the crew for a trip to the Moon. Also on board, as inadvertent stowaways, are his assistant and his secretary; and none of them are aware that the inventor is actually a Lunarian explorer sent to Earth by the dying Lunar civilization and the only remaining male member of that civilization.
Aliens from Outer Space are slowly switching places with real humans -- one of the first being a young man about to get married. Slowly, his new wife realizes something is wrong, and her suspicions are confirmed when her husband's odd behaviour begins to show up in other townspeople.
After his wife and her blind sister have died under his care, a doctor's young daughter is kidnapped and reported as buried alive, leaving him with mere hours to find and rescue her.
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.
An astronaut returns to Earth as the no-pulse host of an alien monster's embryos; he is discovered by a loony farmer who find ways to feed his new critter.
Industrialist François Delambre is called late at night by his sister-in-law, Helene, who tells him that she has just killed her husband. Reluctant at first, she eventually explains to the police that he invented a matter transportation apparatus and, while experimenting on himself, a fly entered the chamber.
When an abused wife grows to giant size because of an alien encounter and an aborted murder attempt, she goes after her cheating husband with revenge on her mind.
After Jonathan Harker attacks Dracula at his castle, the vampire travels to a nearby city, where he preys on the family of Harker's fiancée. The only one who may be able to protect them is Dr. van Helsing, Harker's friend and fellow-student of vampires, who is determined to destroy Dracula, whatever the cost.
American professor John Holden arrives in London for a conference on parapsychology only to discover that the colleague he was supposed to meet was killed in a freak accident the day before. It turns out that the deceased had been investigating a cult lead by Dr. Julian Karswell. Though a skeptic, Holden is suspicious of the devil-worshiping Karswell. Following a trail of mysterious manuscripts, Holden enters a world that makes him question his faith in science.
When men on a photo safari stumble into a misanthropic doctor’s remote camp with a wounded comrade, the doctor's restless wife supplements her usual pursuit (voodoo, especially as a way to off her husband) with a new one: seduction. As men lose their hearts (sometimes literally) to the alluring voodoo priestess, she embarks on a killing spree that turns the jungle blood red.
A test pilot is missing and a search party is sent out in the jungles of Mexico; however, while searching they uncover a monster in the jungle who became this way due to a dose of radioactivity.
Baron Victor Frankenstein has discovered life's secret and unleashed a blood-curdling chain of events resulting from his creation: a cursed creature with a horrid face — and a tendency to kill.
A giant prehistoric praying mantis, recently freed from the Arctic ice, voraciously preys on American military at the DEW Line and works its way south.