Opening with a close-up of the crow’s feet around its subject’s eyes and expanding to reveal her Botox-frozen upper lip, this documentary portrait celebrates Saint Joan the Resilient, Showbiz Survivor. Ricki Stern and Annie Sundberg dogged the indomitable stand-up comic throughout the course of her 76th year—a typically hectic period during which Rivers lurched from disappointment to triumph and back. For all the frenzied activity, A Piece of Work is less informative dish than infomercializing cliché. It may be a revelation to see an entire wall in Rivers’ Louis XIV–style apartment devoted to the card catalog in which she files all her jokes; it’s less illuminating to be told, repeatedly, that a performer craves attention. Nice to know that Rivers is a real person (she comes across as a warm, unembarrassed egomaniac), but it’s the character she invented and plays that makes her interesting. Stern and Sundberg don’t provide much context, but they are not alone in their disinclination to ponder their subject’s art; considering that Rivers is one of the few women capable of holding her own against the vicious spritzmeisters of the Friars Club, she remains remarkably un-theorized by culture critics. At one point, Rivers’ daughter, Melissa, addresses her rivalry with the entity she calls “The Career,” as in her mother’s. There’s plenty of that in Joan Rivers: A Piece of Work, but I wouldn’t have minded a bit more of Joan Rivers: The Text.