Les Blank's film about the making of Werner Herzog's Fitzcarraldo is a fascinating portrait of a filmmaker pushed to the outer edge of sanity by a difficult film shoot, and by his obsession with seeing his vision captured on the screen. Just as the film Herzog is making shows a man (Fitzcarraldo, played by Klaus Kinski) whose passion for opera drives him to a mad and self-destructive act of incredible hubris, the film Blank has made shows a man (Herzog) whose passion for his own art drives him to a similar mad and self-destructive act. Like Hearts of Darkness (Fax Bahr and George Hickenlooper's invaluable document of the making of Francis Ford Coppola's Apocalypse Now), Burden of Dreams paints a somewhat troubling picture of a fiercely intelligent and supremely talented, but megalomaniacal filmmaker, who will stop at nothing to see his brilliant vision realized. The profound respect that Herzog professes to have for the tribal culture Amazonian Indians stands in sharp contrast to the way they are treated on his set, and Blank effectively captures this disparity. He also captures the degradation of Herzog's keen mind, as the jungle apparently begins to drive him mad. "Nature here is vile and base," he explains, as the elements threaten to derail his film, "The trees are in misery. The birds here are in misery. I don't think they sing -- they just screech in pain." Late in the shoot, as the filming hits snag after snag, Herzog laments, with a rueful smile, "I shouldn't make movies anymore. I should go to a lunatic asylum right away." Burden of Dreams is a tale of obsession as compelling and disturbing as the film it documents.