In 1958 Art Kane, at the time one of the most important young art directors in New York, was asked to provide a contribution to a special jazz issue of the magazine Esquire. Kane, who had never taken a photograph professionally in his life, had the brilliant idea of making a photo of 'everyone'. He asked all the important jazz musicians in New York to meet one summer morning. Amazingly enough, Dizzy Gillespie, Charles Mingus, Thelonious Monk, Marian McPartland, Maxine Sullivan, Art Blakey, Milt Hinton, Count Basie, Sonny Rollins, Coleman Hawkins, Lester Young and many others turned up and a truly historic document was born. A Great Day in Harlem presents, like the photo on which it is based, a striking cross-section of the people and styles that together shaped the development of jazz to the avant-garde. The film comprises conversations with and about a number of jazz greats, archive footage of performances and a rare treasury of home-movie material that has never been seen before, shot during the photo session in 1958. What the producer/director Jean Bach wanted to emphasise was the mutual admiration and respect of the jazz musicians. Another motif was the observation that every day chunks of American culture disappear and that the influence of former stars on their successors often goes unnoticed. The film tells the story of what has been called America's only original art form.