 Six miles longer than the English Channel swim, the 28.5 mile swimming race around Manhattan Island is the physical equivalent of running three consecutive road marathons. If the athletic challenge is not enough, the swimmers have to dodge ocean liners, youths throwing rocks, used hypodermic syringes and other UFOs: Unidentified Floating Objects. In August 1994, nine swimmers took up this challenge. They had to complete the course in just ten hours or be disqualified. Wearing no more protection than a thin layer of grease, they raced up New York s East River, along the Harlem River and down the Hudson. Only seven finished. Its like climbing Mt. Everest; they do it "because its there". No cash prizes are given, just the accolade of completing the toughest swimming race in the world. The Big Swim is leavened with stories about the rivers and their notorious pollution. From restaurant chefs to sports fishermen we hear of the improvements to the rivers  water quality. And from New York City s toxic cops (garbagemen who wear guns and carry US Marshall s badges) we hear of the continuing problems, especially the illegal dumping of medical waste. Above, all this film is about the extraordinary swimmers who have the character and endurance to complete this; one of the toughest races in the world.