Four Animal Rights activists break into their local zoo and free all the alligators in the Reptile House. This turns out to be a bad idea as two are soon eaten alive by killer Amazonian caimans, who then make a speedy exit into the nearby countryside. One of the group confesses everything to the local vet, who has been roped in to the 'gator hunt as the nearest local thing to an expert on the creatures. He's having problems with the police and the army who both want to shoot the 'gators once and for all, while he merely wants to tranquillise them and return them to the zoo.