Centuries of global warming have caused the polar ice caps to melt, flooding the earth as civilization is left adrift. The inhabitants of this once-flourishing planet cling to life on incredible floating cities, their existence constantly threatened by Smokers--bands of marauding pirates who roam the featureless surface of Waterworld. For the survivors, one chance remains: a solitary hero, known only as the Mariner. Battling the Smokers and their ruthless leader, the Deacon, the Mariner sets out with a beautiful woman and a mysterious little girl on a search for a new beginning.