In August 1970, 600,000 people, the largest audience in the history of pop music, attended the Isle Of Wight Festival and experienced the debut performance of a new "supergroup": Emerson, Lake & Palmer. With a spectacular stage show that included real cannons being fired over the heads of the audience they became overnight stars with the press raving about their virtuosity and daring. Intercut with the live footage from the show, this film also features brand new interviews with Keith Emerson, Greg Lake and Carl Palmer as well as their then manager John Gaydon and creates a vivid portrait of the birth of a band.