In the Salton Sea, an underwater earthquake causes a crevice to open, releasing prehistoric giant mollusks. A rescue training parachute jump is conducted, but the patrol boat sent to pick up the jumper finds only a floating parachute. One sailor dives in but disappears. The other sailor screams in terror as something rises from the water.
The psychic sends the prostitute back in time to find out about her past-life experiences. She goes back as Helene, a woman from the Middle Ages who is to die at dawn under suspicion of being a witch. In an attempt to save Diana (the prostitute) and keep all of time from being distorted, Quintis (the psychic) goes back in time to convince Helene to let herself be killed. If she avoids her death, it will change history.
Le professeur Charles Conway est un savant fou qui espère découvrir le secret de la jeunesse éternelle en faisant des expériences sur des glandes situées dans le cerveau. Il utilise comme cobayes des personnes dépressives, sans familles et sans attaches, qui pensent être soignées pour leur dépression. Toutefois, les expériences du Pr. Conway tournent mal et ses cobayes deviennent des sortes de zombies…
The mysterious disappearance of Jim Wheatley, while exploring the "cave of the dead" near a Mexican village, brings his sister, Gina, and her husband, Dan Matthews, to the territory to search for him. Embittered, crippled Pete Morgan insists on going along and reminds Dan that his condition is Dan's fault since it happened in an accident in which Pete saved Dan's life. Plus, Gina was Pete's sweetheart before the accident.
The late Dr. Campbell was experimenting with vampire bat blood just before his death. Fellow doctor Beecher finds a bottle of pills among Dr. Campbell's effects and takes them home. Dr. Beecher's daughter accidentally substitutes the vampire blood pills for her father's migraine tablets. As a result, the kindly Dr. Beecher starts having blackouts from the pills, making him change into a bloodthirsty monster by night.
Marta revient après des années d'absence dans l'hacienda familiale de la Sierra Negra. Mais c'est un retour bien funeste pour la jeune femme car sa tante bien-aimée est morte, emportée par une mystérieuse maladie. Accablée par le chagrin, Marta est inconsolable, et ne comprend que trop tard, qu'elle est la proie du Comte Duval, un vampire assoiffé de sang.
A pair of treasure hunters, which includes the beautiful but ruthless Marilyn Blanchard (Marla English), discover gold in the voodoo idol of a tribe of the African jungle. Hoping to find more such treasures, they con the innocent Ted Bronson (Mike Connors) into acting as a jungle guide and leading them to the tribe that made the idol.
A group of scientists land on a remote island in the Pacific Ocean to search for the previous expedition that disappeared without a trace and to continue their research on the effects of radiation from the Bikini Atoll nuclear tests on the island's plant and sea life. They learn to their horror that the earlier group have been killed and eaten by two mutated, intelligent giant crabs, who have also absorbed the minds of their victims and can speak telepathically in the voices of their victims.
The film opens with newspaper photojournalist Audrey Aimes (Castle) accidentally stumbling upon a small town in Illinois which has been inexplicably destroyed. All 150 people in the town are missing, and the evidence indicates they are dead. Incredibly, the local fields are also barren, as if a swarm of locusts had eaten all the crops. Aimes suspects that the military is covering something up, and travels to a nearby United States Department of Agriculture experimental farm to learn what creature might have caused the agricultural destruction. She meets Dr. Ed Wainwright (Graves), who is experimenting with radiation as a means of growing gigantic fruits and vegetables to end world hunger. Dr. Wainwright reports that there have been a number of mysterious incidents nearby, and that locusts have eaten all the radioactive wheat stored in a nearby grain silo.
Six weeks after the death of her mother, Nancy Perkins' father (Thomas B. Henry) marries Doris (Jeanne Dean), and decides to enroll the eighteen-year-old Nancy (Sandra Harrison) into a boarding school, the Sherwood School for Girls. They are greeted by the principal, Mrs. Thorndyke (Mary Adams), who emphasizes to Nancy that the school is not a corrective institution but a private preparatory school with a very good reputation.
The evil Dr. Krupp, once again trying to get possession of the Aztec princess Xochitl's jewels, hypnotizes her current reincarnation, Flor, to get her to reveal the jewels' location - Xochitl's tomb. Confusion reigns as Krupp and his thugs are opposed by Flor's lover, Dr. Almada, his assistant, and wrestling superhero, El Angel. Krupp finally meets his match, however, when he comes up against Popoca, the warrior mummy who guards Xochitl's tomb.
Test pilot Bruce Barton (Duncan Parkin) is missing and his girlfriend, Susan Winter (Gloria Talbott) organizes a search party, sent out in the jungles of Mexico. The team of scientist Russ Bradford (James Craig), mining expert Martin "Marty" Melville (Lon Chaney Jr.) and pilot Lee Brand (Tom Drake) fly into an unknown territory. While searching the area, however, they uncover giant mutated earth animals such as giant snakes and lizards, behemoth bugs, oversized mammals.
A South Seas island prince is wrongly convicted of murder and executed by having a knife driven into his heart, the result of a plot by a witch doctor (the true murderer) who resented the prince's friendly relations with American scientists stationed on a field laboratory on the island. The prince is buried in a hollow tree trunk and forgotten about until nuclear radiation reanimates him in the form of the "Tabanga", a scowling tree stump. The monster escapes from the laboratory and kills several people, including the witch doctor, whom the Tabanga pushes down a hill to be impaled on his own crown of shark teeth. The creature cannot be stopped, burned, or trapped. Only when a crack rifle shot from one of the scientists drives the knife (which still protrudes from the creature's chest) all the way through its heart does it finally die and sink into the swamp.