Agenor Alves

José Mojica Marins, a director of horror films about the diabolical Coffin Joe, is spending Christmas with friends. Household members go violently mad for no reason: first grandpa, then the hosts' daughters, one of whom, Vilma, is about to get married. Mojica discovers that Vilma's mother made a pact with a witch in order to become pregnant with Vilma, promising this first-born child to Satan; her impending marriage to a human is stirring up things supernatural... (imdb)

Four models after a parade are invited for a few moguls into a yacht ride. At dusk, when they return to the dock, four runaway convicts take the yacht assault and head for an island, taking everyone hostage.