Alligator is a 1980 American independent (film and television) science-fiction natural horror film directed by Lewis Teague and written by John Sayles. It stars Robert Forster, Robin Riker and Michael V. Gazzo. It also includes an appearance by actress Sue Lyon in her last screen role.
Set in Chicago, the film follows a police officer and a reptile expert to track a giant murderous sewer alligator, flushed down the toilet years earlier, that is attacking residents after escaping from the sewers.
Critics lauded the film for its intentional satirizing. A direct-to-video sequel was released in 1991, entitled Alligator II: The Mutation. Despite the title, this film shared no characters or actors with the original, and the plot was essentially a retread of the first film. A tabletop game based on the film was distributed by the Ideal Toy Company in 1980.