After two-and-half hours of hagiography, talking heads, archival footage, still photos, and snatches of his songs, Bob Marley remains elusive in Kevin Macdonald's documentary. Partly because Marley himself doesn't say much except in off-screen interviews, with his gnomic words appearing simultaneously as text on a black screen. But Macdonald does tell a good story: Marley was born the son of a Jamaican teenager and a British philanderer, he endured ostracism in his hometown because of his mixed heritage, discovered music when he and his mother moved to Trenchtown in Kingston, started the Wailers, helped develop reggae out of ska music, struggled for independence against record company owners, adopted the Rastafarian religion, and became, briefly, bigger than the Beatles. Cancer spreading from his big toe did him in in 1982 at the age of 36. Throughout the documentary I was hoping they would play "Redemption Song." They do, and I felt like I understood him a little better.