Alligator is a 1980 natural horror/monster film, set in 1980. It stars Robert Foster, Robin Riker, and Henry Silva.
At a tourist attraction in Florida, a young girl named Marisa Kendall takes a baby alligator home for a pet after witnessing an attack on a gator-wrestler, naming it Ramon. However, while she is at school one day, her animal-hostile father flushes it down the toilet. Twelve years later, Slade Pharmaceutical, a company working on a growth hormone for animals, is dumping their dead test subjects into the sewers. Ramon, who somehow survived in the sewers, begins eating the corpses of the hormone-infected animals, growing to enormous size. He kills and eats two different people at seperate points, one a worker and the other the man who stole the test animals for Slade Pharmaceutical. Detective David Madison(Robert Foster), a police detective known for losing a partner about five years earlier, begins investigating the deaths after each victim's remains appear. Ultimately, he decides to go down into the sewer and investigate, taking the only with him the only person willing to partner with him, Officer Kelly. They encounter the giant Ramon, and Kelly is killed, with Madison escaping with his life. Madison is taken to Marisa Kendall(Robin Riker), a herpetologist and expert on alligators, by Chief Clark(Michael Gazzo), his boss, who tells them that an alligator can't survive in the sewer and that Madison was mistaken With rumors abound about the alligator, Thomas Kemp, a news reporter and one of Madison's press rivals, ventures into the sewer, and is killed by Ramon, taking several photos which were undeniable proof of Madison's claim.
Madison heads an operation to kill the alligator, with Kendall joining to help predict the animal. This fails, however, and Ramon breaks free through concrete, attacking a police officer, before retreating into a pool. Colonel Brock(Henry Silva), an experienced professional big-game hunter and tracker, is flown in and hired to kill Ramon, relieving Madison of the hunt. Meanwhile, Madison continues to work with Kendall on his own, discovering how Ramon grew so large. Slade, leader of the aforementioned company, contacts the mayor, who has Madison fired. Stealing evidence from the station to make a bomb, Madison continues to work with Kendall to kill Ramon, starting a strong, but rocky at first, romance with her. Brock is killed and devoured by Ramon, who goes on to evade police boats and rampages at Slade's daughter's wedding, killing many, including him, his son-in-law, who was responsible for the hormone in Ramon, and the mayor. Madison and Kendall track him to the wedding, realizing that he is heading into the sewer again. Armed with his bomb, Madison, instructing Kendall to where he will climb out, lures Ramon to the proper location and blasts him to pieces with his bomb, barely managing to escape with his life after his manhole is blocked. Reuniting with Marisa, the two stand over Ramon's grave and lament the accident being behind them. Later, another baby alligator ominously drops in the sewer.