Largely unseen since its initial release, Wattstax documents a 1972 benefit concert of the same name, an all-day affair commemorating the 1965 Watts Riots, held at the L.A. Coliseum and featuring artists from the Stax label. As an event, it was conceptually problematic from the start: Only a few years away from financial ruin, Stax had seen many of its most famous acts die or disband since its '60s heyday, when it served as the heart of Memphis soul music. What's more, security measures, presumably necessitated by post-Altamont jitters, restricted fans to distant stadium seats, and even from the best of them, the concert could only have looked like a distant blur of saxophones and afros. But even if Willy Wonka & The Chocolate Factory director Mel Stuart had thrown in only half as many gratuitous (and occasionally leering) crowd-reaction shots, it wouldn't be hard to figure out that Wattstax transcended its limitations. In one amazing sequence, Rufus Thomas prompts a field-rushing act of civil disobedience with a performance of "Do The Funky Chicken," talks the crowd back into the stands, and then coaxes it into retrieving a showboating loiterer, all while wearing an outfit that most would consider far too revealing for a man of his age and girth. It's a rare collision of '60s community spirit, Nixon-era paranoia, and the eternal cool of a Memphis legend who cut hits for Sun Records while Elvis was still driving trucks. Now an invaluable time capsule, the film has to transcend its own conceptual messiness. Constantly cutting away from the main-event concert, Wattstax throws in a gospel number from The Emotions staged at a nearby church, a Johnnie Taylor nightclub performance, a primitive music video from Little Milton, biting comedy from then-up-and-coming Richard Pryor, and extensive man-on-the-street interviews about Watts and black life in general, including contributions from a straight-talking, pre-Love Boat Ted Lange. It's interesting material, even if much of it seems like it would be better off in a film where it didn't cut into electrifying performances by Carla Thomas, The Bar-Kays, The Staple Singers, and others. By the time funkily clad event emcee Jesse Jackson introduces Isaac Hayes, such complaints seem minor. Due to a rights dispute, the original release had to do without Hayes' performance. Restored here, the swaggering "Theme From Shaft" fades into the unsparingly sad state-of-the-community number "Soulsville," beautifully summing up what's come before.