On April 5, 1968, James Brown was the hardest-working jackass in show business. The singer was scheduled to perform in Boston the night after Martin Luther King Jr. was assassinated, and Boston mayor Kevin White decided to have WGBH telecast the concert in the hopes that potential rioters would stay home. That decision left Brown hopping mad about his reduced take at the door, putting him on a collision course with the authorities—and, as David Leaf’s film argues, Brown’s own political enlightenment. Drawing on interviews with civil-rights scholars like Dr. Cornel West and folks who were at the concer—including White and Newsweek critic David Gates—Leaf captures the tension of the day, and he devotes plenty of time to footage from the concert itself. (The film is expanded from the version recently broadcast on VH1.) Leaf somewhat underplays Brown’s level of political engagement before the Boston show, but when you see footage of him a few days later, trying to calm the rioting in D.C., it’ clear he’s a changed man all the same.