In 1993, the Search for Extra Terrestrial Intelligence Project receives a transmission detailing an alien DNA structure, along with instructions on how to splice it with human DNA. The result is Sil, a sensual but deadly creature who can change from a beautiful woman to an armour-plated killing machine in the blink of an eye.

Royal Air Force pilot Lt. Kate Sinclair is on her final flight mission when her jet is shot down over one of the most dangerous rebel strongholds in Afghanistan. She finds refuge in an abandoned underground bunker where deadly man-made creatures known as Ravagers — half-human, half-alien, and hungry for human flesh — are awakened.

Having just returned from a mission to Mars, Commander Ross isn't exactly himself. He's slowly becoming a terrifying alien entity with one goal -- to procreate with human women! When countless women suffer gruesome deaths after bearing half-alien offspring, scientist Laura Baker and hired assassin Press Lennox use Eve, a more tempered alien clone, to find Ross and his brood. Before long Eve escapes to mate with Ross.

A scientist, Dr Hollander, takes his niece Miranda to Mexico in an attempt to reverse the effects of the alien DNA he used to create her. However the treatment goes horribly wrong, and sets Miranda on a killing spree as she sets out to find a mate.

After a Soviet space station crashes into a New York City subway tunnel, a species of venomous spiders is discovered, and soon they mutate to gigantic proportions and wreak havoc on the city.