Ranchera singer Chavela Vargas turned heads in Mexico during the 1950s and ’60s with her butch costumes and emotionally naked performances, stripped of the genre’s characteristic gaiety to reveal only stoic sorrow. As this documentary by Catherine Gund and Daresha Kyi shows, Vargas came by her tragic persona honestly: unloved by her poverty-stricken parents, she lived most of her adulthood in the closet (her macho stage act notwithstanding) and was in the process of drinking herself to death when a new romantic relationship gave her the strength to quit in 1988. Her subsequent professional comeback, including a triumphant theatrical debut in Spain, was well deserved, though the filmmakers allow this last chapter in Vargas’s life to drag on as she makes one farewell performance after another. “She tried as hard as she could to die onstage,” remembers one witness; Vargas nearly succeeded, but then the secret of her musical power was that she threatened to die at the end of every song.