An invaluable record of the Newport Folk Festival, the most important annual showcase for roots music from the late '50s through the next decade, Festival packs an amazing amount of information into its brief running time. Director Murray Lerner assembled footage he and several other cinematographers shot between 1963 and 1966 at Newport. The folk music boom that began in the late '50s with rise to popularity of groups such as the Kingston Trio reached its peak during these years, thanks to one man, Bob Dylan. But Dylan also undid the folk revival when he chose to plug in his guitar at the 1965 Newport Festival and play new, rock-oriented material accompanied by the Paul Butterfield Blues Band. That moment is captured here, along with performances by many of the folk movement's leading lights, among them Joan Baez, Peter, Paul and Mary, Donovan, Judy Collins, and Richard and Mimi Farina. Festival also shows how other genres of music were welcome at Newport, with the inclusion of Johnny Cash, Howlin' Wolf, Son House, the Staples Singers, Mississippi John Hurt, and Sonny Terry. In the case of several veteran blues musicians, Newport provided their first exposure to a white audience outside of the South. The emphasis here is on presenting as many acts as possible, so no numbers are shown in their entirety. There are brief interviews with some of the musicians, but the information on them is largely imparted through their performances. Lerner's cameras also capture the youthful exuberance of the audiences, some of them seen jamming on their own instruments between shows.