Michael Mann’s 2001 epic about Muhammad Ali during a key decade (1964-’74) boasts some unusually fine performances—by Will Smith in the title role, Jon Voight as Howard Cosell, Mario Van Peebles as Malcolm X, and Giancarlo Esposito as the hero’s father—and displays Mann’s usual talent for holding narrative interest over the stretch of a long-winded movie. Furthermore, the boxing sequences seem carried out with a kind of care and fidelity that, based on what I’ve heard from aficionados, was absent from Raging Bull. What’s lacking here is a sustained thematic focus—at least five people worked on the script, including Mann, which may account for the absence of a clear through line—though the spectacle and characters keep one absorbed. R, 158 min.