A time For Drunken Horses; <br></br> Aguirre, Wrath Of God (PG)

There's suffering here on such an unsentimental scale, it's enough to sober anyone up

A Time for Drunken Horses (PG) opens with a written statement from its writer-director, Bahman Ghobadi. He says that the film is "a humble tribute to my cultural heritage", and that he hopes it will promote interest in the plight of the Kurds. You don't get that at the start of Planet of the Apes. A film with a purpose? A film that's trying to draw our attention to a lifestyle outside our experience? I'd practically forgotten that films were about anything except Tim Roth dressed as a gorillagram.

Ghobadi's debut feature is the story of Ayoub, an orphaned boy who lives in a Kurdish village near the Iran-Iraq border. He has to support his family, and when he learns that his disabled brother Madi, a 15-year-old with the body of a toddler, needs an expensive operation to survive, he joins a gang of smugglers. This entails taking goods across the mountains and over the border, in conditions so forbidding that the mules need to have their water spiked with alcohol to endure the flaying cold – hence the title. One bitter irony is that the mules' main cargo is massive industrial tyres: a primitive form of transport is being used to service a modern form. Ayoub's world seems so distant from our own that it's shaming to be reminded that he's part of it. Seeing the numerals "1994" embroidered on one of Madi's jumpers is another jolt – this is no period drama.

It's a fair bet that the film won't have audiences queuing round the block, but there are glimmers of humour to offset the bleakness, and currents of warmth amid the snow. In one scene the children are in the back of a lorry, with no access to water, and Madi's brother and sister show him how to generate some saliva so he can swallow his pill. It's the mundane, slightly unsavoury way in which they demonstrate their familial love that makes it so terribly moving.

Ghobadi and his unself-conscious actors never force any emotion. I had a lump in my throat when Madi addressed Ayoub – his younger brother – as Dad, but the dialogue passed in an instant.

If A Time for Drunken Horses is unsentimental, it may be because Ghobadi has set it in his home village, and he points out in his declaration of intent that "these people are not figments of my imagination": he encountered juvenile smugglers while researching a previous short film. He's also revealed in an interview that the actor who plays Madi will die, like his character, if he doesn't have an operation he can't afford. Having said all that, A Time for Drunken Horses is a crafted piece of fiction with elegantly composed shots. But for much of it – when the smugglers kick the mules too intoxicated to keep walking, when Madi bawls as a doctor gives him an injection – it's a struggle to persuade yourself that you're not watching a documentary.

The NFT's Warner Herzog retrospective gets underway with Aguirre, Wrath Of God (PG). A magnificent film from 1972, it follows a band of conquistadors and their slaves as they set off by raft in search of El Dorado. If the natives' arrows, the treacherous river and the Peruvian climate weren't enough to contend with, there's a mutinous madman played by Klaus Kinski on board, a scowling, skulking Richard III, who looks as if he might bite a chunk out of your leg at any moment.

The film begins as a rather dated historical adventure, but as the conquistadors' hope and supplies run out, it warps into a black comedy with fantastic surreal imagery. There can't be many funnier pictures of human vanity than that of a fat nobleman deciding that he has conquered the jungle around him, just because he and a dozen men are drifting through it along a sluggish, mud-brown river. "Our country is already six times larger than Spain," he puffs. Priceless.

n.barber@independent.co.uk