A small town in Texas finds itself under attack from a hungry, fifty-foot-long gila monster. No longer content to forage in the desert, the giant lizard begins chomping on motorists and train passengers before descending upon the town itself. Only Chase Winstead, a quick-thinking mechanic, can save the town from being wiped out.

Trapped on a remote island by a hurricane, a group discover a doctor has been experimenting on creating half sized humans. Unfortunately, his experiments have also created giant shrews, who when they have run out of small animals to eat, turn on the humans.