At the LFF: "Sister"

From her first features, we might deduce that Swiss filmmaker Ursula Meier has a thing for unusual configurations of the family unit. Her eyecatching 2008 film Home saw a clan living in isolation at the side of an abandoned motorway project, while her latest Sister concentrates on a pair of kids who've apparently been abandoned by their parents and now eke out an existence in the foothills, literal and economic, of an Alpine ski resort. While Louise (Léa Seydoux) disappears off with a no-good boyfriend who beats her, her 12-year-old sibling Simon (Kacey Mottet-Klein) ventures up the mountain to steal and fence the skis and sandwiches of rich holidaymakers, anything to help the pair of them get by.

For a while, as in Home, we're offered no more than a study of a place and its routines. Simon befriends a Scottish chef (Martin Compston) working in the kitchens of one of the resort's restaurants, then begins to insinuate himself into the lives of a British family headed by Gillian Anderson. The actors draw you in. Mottet-Klein, crafty and supple, is afforded the run of these locations like a young Belmondo; Seydoux, after several years' worth of scarcely memorable waifs and ingenues, gives what's perhaps the first mature performance of her career. She has to, to make complete and emotionally satisfying sense of the one major narrative revelation here, which comes around the hour mark, casting everything that's come before in a new light.

In some ways, Sister is a, well, sister piece to Home. The family in Meier's earlier film were at the mercy of the world whizzing past their doorstep, eventually descending into a form of madness. The consequences here aren't quite as dramatic, but it's clear from the boyfriend's hopping from one car to the next, and from the schoolboy black market Simon operates within, that everybody's trading up, leaving the siblings - like their forerunners in the Meier filmography - far behind. At one point late on, Simon is scooped up by an irate chef and tossed in a cable car full of trash bags; we grasp immediately that this is pretty much all that trickles down the mountainside to the townsfolk below.

And still Simon and Louise persist, trying to get a foothold in the face of the universe's apparent indifference. Sister refuses sentimentality, with its Bressonian inserts of notes being counted out and handfuls of loose change, and through its supremely eloquent, almost graph-like Agnès Godard compositions, showing its central couple as dots dwarfed by one or more of the region's towering peaks, left to tramp through mud and dust while their peers and contemporaries cut a dash through virgin snow. Yet whatever their relationship within the frame, the bond between the two cannot quite be snapped or severed: all these children have in this world is each other.

Sister screens on Friday 12 at 9pm at the Curzon Mayfair, and again on Tue 16 at the Vue West End; it opens in the UK in November.