Freelance reporter Jennifer and her two friends, Karen and Vicki, accept an invitation for cheap room and board in a large farmhouse offered by a friendly, but shady, museum owner named Ernest Keller since all the motels in and around town are booked for a holiday parade fair Jennifer is covering. But unknown to the women, some unseen "thing" has been living in the basement of the house for over 20 years and is looked after by Keller and his shy sister Virginia, in which the "thing" soon gets out and begins harassing and killing the women one by one in various violent, but seemingly accidental, means.

Ramon the alligator is flushed down the toilet as a baby and grows into a gargantuan monster by eating the corpses of laboratory animals who have undergone dubious hormone experiments, thus providing all the ecological and social subtext that one could possibly wish for, even if one doesn't normally go for films about giant alligators eating people left, right, and center--which is the inevitable and tragic result of Ramon's decision that the outside world looks rather more interesting than the sewers....

The old teen rebel saga is updated for the rap crowd, unfortunately rapper Vanilla Ice is the teen. Ice shows up on a neon-yellow motorcycle which gets everyone's attention, including the female honor student who has never had a rebellious bone in her body.