As any student of rock history knows, Joplin first achieved notoriety as a member of Big Brother and the Holding Company, a ragged band of psychedelic rowdies that she jettisoned once her fame began to eclipse theirs. This documentary juxtaposes poignant archival footage of Joplin and BB back in the day with current reminiscences by the group’s members. One particularly hilarious sequence has each musician remembering what Joplin wore to her first rehearsal; needless to say, each recalls a completely different outfit. Thankfully, we don’t have to trust anyone’s memory about the quality of the music this team produced, since there are some swell performances here that capture Big Brother and Janis in all their untamed, freak-flag-flying glory. To their credit, the assorted Brothers don’t come off as especially bitter about Joplin’s having left the band after the release of 1968’s seminal Cheap Thrills album. Maybe it’s because they know that, as critic Lenny Kaye points out, the Big Brother period is still where most Joplin junkies turn when they want a piece of their collective heart jump-started.