By all accounts Chicago blues legend Muddy Waters (aka McKinley Morganfield) led a fascinating life, spanning the jim crow era and civil rights movement and providing the vital link between Mississippi Delta blues and its urban electric counterpart. Unfortunately this documentary by Morgan Neville and Robert Gordon (author of the latest Waters biography) barely hints at the bluesman’s social and artistic relevance, presenting a cursory assortment of interviews with his kin, friends, and celebrity fans, along with old photos and concert clips. Any sort of focus would have helped—on the musician’s long and rocky relationship with Chess Records, for instance, or the shift in his fan base from black to white. By casting a rich, emotional career and the sound it produced in such a standard-issue format, Neville and Gordon slight the man they’re trying to honor. 60 min.