Each year the population of sleepy Lake Victoria, Arizona explodes from 5,000 to 50,000 residents for the annual Spring Break celebration. But then, an earthquake opens an underwater chasm, releasing an enormous swarm of ancient Piranha that have been dormant for thousands of years, now with a taste for human flesh. This year, there's something more to worry about than the usual hangovers and complaints from locals, a new type of terror is about to be cut loose on Lake Victoria.
A scientist comes to believe that evil is a disease of the blood and that the flesh of a skeleton he has brought back from New Guinea contains it in a pure form. Convinced that his wife, a Folies Bergere dancer who went insane, manifested this evil, he is terrified that it will be passed on to their daughter. He tries to use the skeleton's blood to immunise her against this eventuality, but his attempt has anything but the desired result.
A game warden moves his family to Lake Placid, once the site of deadly crocodile attacks. Locals assure him the crocs are gone, but his mischievous young son finds a few baby crocs and begins feeding them. They quickly grow into very big adults and start attacking the game warden's family and nearby town.
The spaceship AAB-Gamma is dispatched from FAFC headquarters in Japan to make a landing on the planet Mars and investigate reports of UFOs in the area. As they near the red planet, they encounter a mysterious UFO that coats the ship's hull with unusual spores. Taking one of the specimens back to earth, it soon develops and grows into a giant chicken-lizard-alien monster that tramples Japan.
Five teenagers embark on a boating trip off the coast of Florida. The teens get hopelessly lost at sea after they get caught in a fierce storm. Fortunately, the quintet stumble across an abandoned yacht in the middle of the ocean with a mysterious biology lab on board it. Unfortunately, there are also ferocious mutated prehistoric fish running amok on the yacht. Will any of the teens survive this harrowing ordeal?
In 1978 Oregon, Ben and Jules inherit an abandoned coastal property from Ben's late mother, who's never mentioned it. The untouched house has been kept a secret for 40 years and comes with a beautiful private cove and beach. Jules searches for answers while Ben unwittingly awakens a fiercely protective creature.
Radioactive waste dumped off the coastline creates mutant monsters. The beasts attack slumber parties, beaches, tourists, and terrorize a waterfront community as a scientist, his daughter, her boyfriend and the local police try to find a way to stop them.
In an effort to find an economic means of purifying salt water, a joint U.S.-Japanese military command is set up on an isolated Japanese island where an unusual salt water lake is situated. However, their purifying experiments arouse the prehistoric monster Obaki from hibernation at the lake's bottom, and it proceeds to attack Japan. Although made by a U.S. independent film company, this film was based on a Japanese Toho monster film of 1958, "Daikaiju Varan", from which all of the monster effects scenes and a few incidental dramatic shots were edited into it.
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.
A mysterious hypnotist reverts his beautiful assistant back into the form of a prehistoric sea monster that she was in a past life.
A recently single mother must learn to let go of her fear and obsession about her abusive husband in order to save her son from the hands of a mysterious creature from the woods.
A loner dork gets fed up with the monotony of his existence under the shadow of his narcissistic friend. Forcing the the pair to reevaluate their place in life.
A group of thieves have the tables turned on them during a home invasion. Hidden in the basement they find the remains of secret viral lab experiments gone savagely wrong. Now they must escape before they are infected with a new strain of virus that turns its victims into mutated psychopaths.
Some fishermen are attacked in the Louisiana swamps. When the word gets out of a mysterious Bigfoot-type creature, two researchers come to a small town to study and hopefully discover what the beast is. Their research from some farmers help the two men to learn that the creature may be a very angry and murderous missing link.
Marine atomic tests cause changes in the ocean's ecosystem resulting in dangerous blobs of radiation and the resurrection of a dormant dinosaur which threatens London.
When a narcotics deal goes sour and a suspect disappears, leaving only his clothes, Tokyo police question his wife and stake out the nightclub where she works.
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.
A United Nations investigator crosses paths with a pair of psychic sisters on his way to Trollenberg observatory in the Swiss Alps, which has been plagued by a series of mountaineer disappearances that may be related to a radioactive cloud at the mountain's south face.
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.
A rural Colombian village is attacked by a horrible sea serpent, aroused by industrial pollution of a nearby lake. Based on a real event that took place in June of 1971.