Twenty-five years after the release of his critically-acclaimed Graceland, Paul Simon goes back to South Africa and reunites with the musicians with whom he collaborated in a documentary by filmmaker Joe Berlinger. The trip has more than passing significance: When Simon traveled to Africa in 1985 to record Graceland with local artists, he was accused of breaking the UN cultural boycott of South Africa. The film, which premiered at this year's Sundance Film Festival, looks at the controversy and its aftermath.