The film takes place at the beginning of the 19th century. Oberlus (Everett McGill), a harpooner on a whaling ship, is regularly subjected to ridicule and abuse by other sailors. The right half of his face is bizarrely disfigured and covered with hummocky outgrowths, which leads him to being nicknamed Iguana. One night, after a brutal beating, Oberlus escapes to the uninhabited Española Island. He is soon discovered by a team led by captain Gamboa (Fabio Testi). Gamboa brutally tortures Oberlus and ties him up for further punishment, but Iguana manages to escape and hides himself in a cave. The ship leaves the island and Gamboa orders that sailor Sebastian (Michael Madsen) be tied to a post on the coast as punishment for letting Iguana escape. Oberlus finds Sebastian and proclaims himself "King of Hood Island" and Sebastian his first slave, forcing him to cook his food.