Waterworld (1995)

After the polar ice caps melt, the world is submerged, and the Mariner, adapted with gills, navigates the ocean. Reluctantly befriending Helen and Enola, he aids their escape from a hostile artificial island. Pursued by the sinister Smokers, they believe Enola holds the key to Dryland. This action-adventure film starring Kevin Costner is a must-watch journey through a waterlogged world.