As a drum roll before James Mangold’s A Complete Unknown’s Christmas release, this powerful doc shows Dylan’s transition from troubadour to rock star, accompanied by Joan Baez, Johnny Cash and the Paul Butterfield Blues Band. Murray Lerner and his crew capture vital performances in images of rapt attentiveness. The sound mix is crisp, the black-and-white photography is shimmering, and the songs are heard in all their enigmatic glory, performed by an artist with uncanny gifts. (dir. Murray Lerner, U.S., 2007, 83m)