There’s no exposition at the start of Gerry – nor a title, for that matter, let alone credits. Just Matt Damon and Casey Affleck’s battered auto cruising along a freeway, mountain spectacle glowing all around, Arvo Pärt gently soothing the soundtrack. Are they friends? Lovers? On a car share? Let’s not hurry things, the camera tuts, picking out the grime on the windshield and the flaring sun. For the moment we’re the ones who have been deposited, ignorant and demanding, in a strange, indifferent setting. Matt and Casey – both of whose characters are named Gerry – park at a wilderness trail and set off. ‘Hey, Gerry,’ says Matt (the film’s first words). They leave the path, walk, trot, race each other through the brush, and collapse exhausted in the dirt. As the light dips, they head for where the path could be. We cut to a long shot. They are a very long way from anything, and will be for another four days to come. The camera drifts to the left. Look at the rock! Clouds swallow mountains. The wind wails.

It remains to be seen if Gus Van Sant has said goodbye for good to the regrettable high Hollywood tropes of Finding Forrester (2000) and Good Will Hunting (1997). But Gerry and its successor, the Cannes triumph Elephant (2003), seem to stem from an aesthetically and politically bolder space – one closer, perhaps, to the messier, more poetic voice of Drugstore Cowboy (1989) or My Own Private Idaho (1991).

In fact these new pictures are concerned with the same subject as the great majority of Van Sant’s films, whatever their style: boys trying to pick a path through the emotional and practical vicissitudes of maturity. Gerry takes the pleasure in American pastoral evident in Idaho and Even Cowgirls Get The Blues (1993), and elevates it to the sublime: the two Gerrys wander, plan, build fires and get trapped on boulders, all against the gorgeous terror of the American landscape (photographed in Argentina and Death Valley). And that’s almost all there is of a plot.

The film hinges on this double perception of its situation, teasing us to choose between the two Gerrys’ points of view and the impassive desert rocks. Do we think ‘how forbidding the terrain and late the afternoon’ or ‘how stunning the scenery and lovely the light’? It’s a choice neatly presented in a pair of 360 degree pans two-thirds of the way in. First we circle around Casey, by now exhausted, thirsty, sunburnt and delirious. If the camera is a vulture, it decides he isn’t worth the effort. Then we take in the vista from where he sits: unyielding in its beauty, the land seems less an opponent than a glorious companion.

If the situation could be from Beckett, the improvised dialogue can’t match his dramatic power. Nevertheless, the boys’ use of the word ‘Gerry’ as an all-purpose filler (‘there were so many Gerrys along the way’ or ‘we totally Gerryed the mountain scoutabout’) has the same effect as their identical names in depleting the value of identity and culture. The long, often static takes, the stately plod of the editing, and the placement of the camera’s attention on the setting rather than the actors, reinforce this diminution.

Yet the equally frequent, equally long close-ups of the Gerrys’ feet and faces as they schlep up cliffs or across salt flats, to the accompaniment of their footfalls and breathing, has the contradictory effect of emphasising their ordeal above its surroundings; flashbacks, hallucinations and time-lapse effects give us no choice but to see the situation through their minds. It isn’t a conflict the film resolves, and by the time of its desperate climactic embrace, some viewers will have tired of the conceit. As the ordeal ends, one Gerry looks out at the wilderness through a window. Like Dustin Hoffman at the end of Rain Man, he doesn’t look back.