Rats Night of Terror . 1984

Exploitation / Sci-Fi / Horror . In a post-apocalyptic earth, where most of humanity lives underground, a group of surface people stumble upon an abandoned lab that was trying to bring life back to the earth's surface, but the place is run over by vicious rats.
One hundred years after a nuclear war has devastated the planet, society has been reborn into two factions; the underground society and the scavangers above in the wastelands. A group of scavangers on bikes come across a town infested with flesh eating rats, and soon the gore is spilling everywhere.