"Even as we were thrown in jail someone would sing a song," recalls Rep. John Lewis (D-Ga.) in this history of the civil-rights movement and its freedom music, featuring potent performances by John Legend, the Roots, Wyclef Jean, Angie Stone, Joss Stone, Mary Mary, and Anthony Hamilton and the Blind Boys of Alabama. The documentary charts the years from the 1955 Montgomery, Ala., bus boycott to 1968 MLK Jr. assassination; and includes remarks from Harry Belafonte, Julian Bond and Andrew Young.