It is the custom now for everyone in the film business to describe film-makers as “storytellers”. But even leaving aside the fact that so many film-makers are not very good at the old-fashioned business of storytelling, the fact is that cinema does not have to be about story, however uncommercial an idea that seems.

The Argentinian director Lisandro Alonso is a case in point: his work is challenging and opaque and taken an uncompromisingly andante pace and yes, it is probably destined to be shown at festivals. But it is also weirdly hypnotic and exalted and magnificent in its way, and often has nothing do with story. His last movie, with Viggo Mortensen, entitled Jauja, was a case in point. Now he has come to Cannes with his experimentally non-narrative meditation on the global condition of indigenous peoples. It is entirely fascinating, though undoubtedly it requires the audience to recalibrate their own consumption-tempo and attention span stamina.

We begin with an eerily slow black-and-white sequence which appears to be an old-fashioned western, with Viggo Mortensen playing some stranger arriving in a windblown American town in the Old West. From there we shift, in full colour, to a Native American reservation in the contemporary US, where a Native American police officer picks up an actor from that movie by the side of the road with car trouble. This same officer gives the actor a ride to a nearby school where her niece Sadie coaches basketball. Then she resumes her increasingly dreary workload: picking up a violent drunk with a knife and another drunk driver and attending to reports of a fistfight at a casino.

But she seems disinclined to answer her dispatcher’s calls for information and this dispatcher’s radio calls seem like wan calls into an empty void. Meanwhile, young Sadie, herself apparently tired of life, calls on her grandfather to give her a potion which will give her deliverance: a brew which causes her soul to change into a large bird which flies through time and space to the Brazilian jungle of the early 70s, where the member of some religious community kills someone in a knife fight and escapes to where gold is being prospected and meets his own strange destiny with the bird-soul as witness.

The entirely bizarre narrative or anti-narrative conveys nothing of the film’s dreamy effect, its prose-poetic procedure or its status as artwork. It’s a film which moves laterally away from its starting point and more or less ignores those Aristotelian unities of time and place that most films stick to. And the title is another enigmatic thing about it. There is certainly no obvious “eureka” moment of discovery or understanding. But there is a sort of sensory perception, a feeling that through drifting downstream along the river course of this film and gazing at the foliage on either bank, some progress of the soul is being achieved. It is an enriching experience.