First Comes The Slither, Then Comes The Slaughter.
A set of vipers has been taken by scientists to mutate them to make a cure for cancer. As their experiment goes awry, the vipers escape into the woods - they're not only biting people, they're actually killing people, in a little town.
Cancer-terminal tycoon Peter Murdoch's secret Wexel Hall Pharmaceuticals lab has developed a blood orchid extract cure. To examine why it works optimally in snakes, they also bread a super-anaconda strain. But the original pair escapes, leaving a bloody trail of human corpses. Murdoch runs, instructing his staff to clean up. They keep failing and being eaten like unsuspecting locals, some alive, even after enlisting ruthless big game hunter Hammett. The fast-growing pregnant monster sheds its skin, thus disabling the only tracking device they have.
A group of American tourists heading down an African river make a brief stop at Snake Island, an island that has been virtually abandoned for years. When they end up getting trapped on the island overnight, they find thousands of deadly snakes intent on reclaiming the tropical island for themselves.
The blood orchid - a rare flower that could hold the secret of eternal life and be worth a fortune to the company that finds it first. Led by a pharmaceutical research team, a scientific expedition sets out to go and explore deep into the jungles of Borneo to locate and bring back samples of the legendary plant. Battling through rainstorms to make their way upriver, the group encounters poisonous insects and a ferocious crocodile, only to discover they're being stalked by an even greater danger: a gathering of giant anacondas. Heat-sensing, fifty-foot-long flesh eaters that will go after anyone that crosses in their path.
After an overly ambitious businessman transports an 80-foot python to the United States, the beast escapes and starts to leave behind a trail of human victims. An FBI agent and a snake specialist come up with a plot to combat the creature by pitting it against a bioengineered, 70-foot boa constrictor. It's two great snakes that snake great together!
Paleontologist Robert Trenton is called to Northeastern Antarctica near the Indian Ocean to help the FBI build an underground maximum-security military base and prison for the world's most dangerous criminals and terrorists, which is dubbed "New Alcatrax" by the staff. While building the prison, the staff accidentally awaken and unleash a prehistoric Boa Constrictor from its 200 year hibernation.
An object is found that points to the secret of eternal youth so a research team is sent to find the fountain only to find it is protected by a giant snake
Mutant snakes survived a terrorist attack on a government laboratory, and they now threaten the town of Santa Mira Springs, California. Seismic activity has brought snakes to the surface, where residents are being bitten. Victims can transmit the virus to healthy persons. The military puts the town under quarantine. Local physicians try to control the epidemic, while the military is primarily concerned with keeping the virus a secret.
Under a powerful Mayan curse, snakes are hatched inside a young woman, slowly devouring her from within. Her only chance for survival is a powerful shaman who lives across the border. With only hours to live, she jumps on a train headed for Los Angeles. Unfortunately for the passengers aboard, they are now trapped, soon to be victims of these flesh-eating vipers.
In the countryside, the boy Alan and his friend Becky steal a creepy wooden box with a powerful voodoo stick inside from his voodooistic neighbor. When the boy draws with the stick, his drunken father is attacked by a snake and vanishes. Years later, Alan and Becky are married to each other; while planting some flowers to celebrate the death of Alan's mother, Becky finds the box buried in the garden and she keeps the stick in her pocket. Meanwhile, five friends are traveling in a monster truck, drinking beer. The driver accidentally runs over Becky, but believes he had hit an animal. When Alan witnesses the hit-and-run and sees his wife dead, he uses the stick seeking revenge against the youngsters.
A hybrid creature - half piranha and half anaconda -- attacks a low-budget horror movie crew on location near her nest when her egg is stolen. Now they must outrun and kill the deadly piranhaconda as well as stop the mad scientist who stole the egg - before they all become dinner.