Mann's typically ambitious film about the former heavyweight champ is both visceral and immensely intelligent. From the virtuoso opening to the climactic re-creation of Ali's 1974 Zaire bout with George Foreman, Mann achieves a thrilling mix of action and analysis, exploiting and transcending both boxing movie and biopic conventions with a master's ease. Crucially, the film is less a psychological study than a case history of America, from the passing of the Civil Rights Act to the end of the Vietnam War. While Smith's Ali is wholly credible as an individual determined to define and remain true to himself, despite a widespread expectation that African-Americans and sportsmen should quietly accept their lot, the character also becomes an index of racial, religious, political and social changes. Most memorably, of course, he alters his name, joins the Nation of Islam, and refuses to fight in Vietnam, risking confusion, contempt and professional catastrophe. Meticulous as ever, Mann gets all this right. Smith, buoyed by a brilliant cast, is funny, sexy, conceited, deceitful, proud, loud and troubled, and he rises superbly to the occasion in the expressive fight scenes.