Here’s the rare music documentary in which the narrative is more interesting than the songs. Detroit-based singer-songwriter Rodriguez recorded two psychedelic pop albums in the early 1970s; he never caught on and eventually dropped out of public life, but his records became legendary among the counterculture of South Africa, which saw in his beatnik persona a model for antiapartheid rebellion. The first half of the movie examines the music’s social impact and fans’ efforts to track down the singer in the 1990s, which director Malik Bendjelloul relates like a good mystery. The second half concerns Rodriguez’s adventures after leaving the music business, an equally compelling story about the art of living.