After eight years since the events of the first film, a scientist has designed a new species of bat genetically designed to be biological weapons in a confrontation between Chechen and Americans.

Genetically mutated bats escape and it's up to a bat expert and the local sheriff to stop them.

An alien virus that once wiped civilizations out in ancient times through out time has returned overnight by a mysterious thunderstorm infecting all the bats in the area causing them grow into grotesque giant carnivore man-eater mons