The Maysles brothers -- unfortunately uncredited -- put together a series of scenes from promo sessions Marlon Brando submitted to. Even though it amounts to found footage, you learn more about Brando as a man and an actor from these fragments than from nearly any other source I've come across.
Above all, he seems startlingly alive. Wary, observant, playing a 3-D game in a 2-D frame, alert to the possibilities of sex. A guy, for sure, but as rawly sensitive as an open wound.
No wonder he later grew fat and baroque; he probably needed the insulation.