Alligator

 

 (wikipedia)

ALLIGATOR-1980-12 years after a stupid father flushes a baby alligator down the toilet, body parts and dead dogs are found by police in the sewer system. Detective Madison (Robert Forster) and his jerky new partner Kelly (Perry Lang) investigate. When Kelly is killed, everyone including his chief (Michael Gazzo) thinks Madison is nuts and incompetent because his partner before Kelly was also killed. Snake expert Dr. Kendall (Robin Riker) isn't much help. 

The first victim is a pet shop owner (Sydney Lassick) who's illegally supplying dogs for experiments. After a sanctimonious reporter (Bart Baverman) is killed and some of his photos show an alligator, an all-out manhunt is launched. The giant lizard bites off the leg of a policeman. The mayor (Jack Carter) calls in Col. Brock (Henry Silva), a pompous big game hunter. Madison ties the mutant to Slade Industrial, run by old fart Mr. Slade (Dean Jagger) who had ties with the corrupt mayor. 

The best part is when the alligator crashes Slade's daughter's wedding. Sue Lyon (in her last movie) has a small role as a reporter as does Mike Mazurki. John Sayles wrote the clever script and Lewis Teague directed before he made bigger budgeted films like CUJO (1983), CAT'S EYE (1985) and THE JEWEL OF THE NILE (1985).

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