An old teacher of mine once said that if you were to dramatize a famous person's life (i.e. make a "biopic"), it would be most effective to stage your story on one day – preferably a critical day of that person's life – rather than try to recount the entire cradle-to-grave scope of their existence.

That's a bit extreme, but I agree to some extent. So, too, does Michael Mann, it seems, as instead of covering the whole first 60 years of Muhammad Ali's time on earth, he focuses on the former boxer's 10 most dramatic: from his victory over Sonny Liston in 1964, winning the heavyweight championship, through his conversion to Islam, his friendship with Malcolm X, his notorious refusal of the Vietnam draft, his first two wives, and finally his momentous bout in 1974 when Ali, at 32, reclaimed the heavyweight title against George Foreman in their legendary "Rumble in the Jungle" fight in Kinshasa, Zaire.

The decade-long time frame is a wise choice: Ali's subsequent bouts with the forgettable Leon Spinks and his slide into the heartbreak of Parkinson's disease are things we don't need to relive. Still and all, Mann seems less interested in telling a story (Ali's character doesn't exactly have an arc) or exploring Ali's inner life than he is in depicting the former Cassius Clay as a symbol of a turbulent time in America, from the ideological '60s to the me-first '70s. Because of his race, because of his fame, because of his integrity, and because of his attitude, Ali is seen by Mann as the embodiment of all the good and all the bad in that era.

Too bad Ali doesn't live up to Mann's – or, for that matter, Ali's – ambitions. Mann revives his groundbreaking visual style from The Insider, but breaks no new ground with them. In the end we're left with a fairly standard biopic.

As for Will Smith in the title role, he finds the essence of Muhammad Ali without lapsing into impersonation. His much-noted muscle gain was crucial to the part, but although he fast-talks like the champ, he doesn't try to imitate Ali's famous rasp or his bug-eyed glower. It's an interesting choice, given that his costar John Voight is rendered completely unrecognizable under pounds of makeup as sportscaster Howard Cosell. (Voight's terrific, by the way.)

Though we may not learn much about Muhammad Ali that we hadn't already guessed – that he loved the limelight, that he was a ladies' man, that he was a great boxer – watching the film is an undeniably visceral and thought-provoking experience. And if nothing else, you'll get a sense of how exhausting a few rounds in the ring can be, even for "The Greatest".