The Fishmen and Their Queen(1995)

Original title: La regina degli uomini pesce

Two teenagers prowl a devastated landscape, polluted by radioactive waste in search for food. On their quest of survival, they meet Socrates, a man who takes them to an island that seems a far cry away from the urban misery they struggled in. But the two youngsters ignore that the island is ruled by a beautiful but ruthless queen whose slaves are the hideous fishmen.