Singer-songwriter Townes van Zandt was at the center of Austin’s outlaw country scene in the 1970s, but, while friends like Waylon Jennings and Steve Earle went on to mainstream stardom, the mercurial Van Zandt retreated into a haze of alcoholism and mental illness. This sympathetic documentary traces his work and life, which was cut short on New Year’s Day 1997, when he was 52.