Self-reflexivity aside, it would be virtually impossible to pinpoint a more intimate documentary mode than a biographical portrait shot by one's closest sibling, and that axiom undergirds Barbara Leibovitz's penetrating look at her older sister: Annie Leibovitz: Life Through a Lens. Camera-in-hand, the elder Leibovitz not only taught Americans how to look at celebrity - single-handedly sculpting the public perceptions of such notables as Mick Jagger, Whoopi Goldberg, Demi Moore, Patti Smith, Hillary Rodham Clinton and dozens of others - but burned into the mass-consciousness indelible views of the Sarajevo and Rwanda massacres. Annie Leibovitz's photographs are iconic and everpresent, but the woman who shot them commands greater elusiveness. Traversing this longstanding barrier with the subject's permission, Barbara visits Annie at the family's rural homestead, amid the latter's strenuous work on a new photographic collection, and begins to reveal, on-camera, the many layers of her sister's personality and world view. The filmmaker is abetted throughout by celebrities who appear, sharing candid insights into the famous photographer and telling recollections of their on-set interactions with her.