Septuagenarian documentary god Patricio Guzmán scored an enormous triumph with 2010's Nostalgia for the Light, one of the most important and under-seen films of the decade. Two things are thus unsurprising: that Nostalgia's 2015 companion piece, The Pearl Button, would fail to match the same heights; and that The Pearl Button would still be a hell of a fine achievement in its own right, re-directing Nostalgia's impulses into new, if familiar channels that result in a wholly new set of observations about the idea of nationhood and the relationship of humans with their cultural past.

Whereas Nostalgia was a film about the desert, The Pearl Button is ultimately a film about water, and it would be worth every minute even if the movie offered only the pleasure of seeing how Guzmán and cinematographer Katell Djian framed and shaped images of water flowing, crashing, dripping, and gently ebbing. The film is as much a meditation on its themes as a discussion of them, and the accumulation of water images is one of the most successfully meditative things about it.

Water is not just a visual motif but a philosophical one, as well; even spiritual, maybe, in Guzmán's conception. In focusing on the human inhabitants of the Tierra del Fuego archipelago, including the last vestiges of the pre-Columbian language users in that part of South America, The Pearl Button naturally focuses on how life on an island is shaped by the sea, from which resources and invaders alike both come. The title itself is a dual reference to Jemmy Button of the Yaghan people, who was trotted around England in the 1830s (and who returned to Tierra del Fuego on the same voyage of the HMS Beagle that brought young naturalist Charles Darwin to prominence), as well as to a button found wedged in the rails used to weight down the bodies sent to drown during Augusto Pinochet's reign, a pair of historical grace notes that both suggest the worst in human behavior, but The Pearl Button takes a more pacific than nihilistic view of the flow of history, even if Guzmán's ultimate theme is to warn us of the history and identity that risk being lost as time marches on.

Starting with Guzmán's own narration, warm and quasi-mystical, The Pearl Button is generally more of a series of reflections than anything analytically focused, and it lacks Nostalgia for the Light's keen sense of specific outrage; even when the film tries its damnedest to address specific question of Chile's tendency to swallow up its own past, The Pearl Button keeps drifting into Big Questions about human civilisations more generally. Speaking privately, I wouldn't have it any other way; one of the privileges of old age is the ability to take the long view, and Guzmán's generous diagnosis of human failing makes for a truly moving and ingenious film even if it lacks the sharp focus or political edge of his best work.