These days, with Floyd Mayweather Jr. gabbing on Live with Kelly and Michael and posting twitpics of his $200,000 betting slips, and with Mike Tyson (yes, sigh, Mike Tyson) launching a reality series, it's hard to conceive of a time when anything a boxer did outside the ring actually, well, mattered. But two new films, both centered on Muhammad Ali's engagement with the Nation of Islam and his legal struggle following his refusal to be drafted, portray a time when a singular fighter and his extraordinary era intersected in profound ways.

HBO's Muhammad Ali's Greatest Fight, which debuts on Oct. 5 and is directed by Stephen Frears (The Queen), is a glossy and engaging docudrama that focuses on the Supreme Court's inner-chamber battles in 1971, when the justices ruled on Ali's appeal of the conviction that had cost him 3½ years of his career and threatened to send him to jail for five more. Frank Langella plays Chief Justice Warren Burger as a venomous closet racist, the pro-establishment defender of President Richard Nixon's increasingly unpopular war in Vietnam, while Chistopher Plummer is a stern-but-wise Justice John Harlan II. An invented subplot centers on Harlan's idealistic young clerk, who discovers the precedent that leads to the Court's overturning Ali's conviction. Ali appears only in archival footage, but those glimpses send a jolt through the film, showing not only how vibrant he was but also the depths of the passions that swirled around him.

That sense is amplified in the richly textured and exhaustively researched The Trials of Muhammad Ali. From the producers of Hoop Dreams and director Bill Siegel (The Weather Underground), the documentary—which opens in selected cities this week—combines archival footage with current-day interviews with figures from Ali's life, including his brother, Rahman; his former wife Khalilah Camacho-Ali; journalist Robert Lipsyte; and Louis Farrakhan. The focus here is also on Ali's out-of-the-ring battles. While the narrative may be familiar, the film includes fresh clips and new voices that make Ali come alive again. For younger viewers who may know the Greatest only in his current state, immobilized and silenced by Parkinson's, that's a gift.

The movies portray the profound intersection of a singular fighter and his extraordinary era.