Leon Gast's Oscar-winning documentary charting the challenge of an ageing Muhammad Ali for George Foreman's World Heavyweight title held in Zaire in 1974. The film explores the impact of Ali's visit to Africa before focusing on the epic fight, dubbed the `Rumble in the Jungle", which has gone down in history as one of the greatest of all time. Spike Lee and Norman Mailer are among the contributors offering personal opinions on its importance to them