A bracingly honest approach to flawed characters makes this small-scale Swiss drama thoroughly involving. And moving too. Most intriguing is how the writers and director have transformed what's essentially a rather dark, bleak story into something involving and emotionally resonant, all without ever turning sentimental.

It's set at the foot of a spectacular Alpine ski resort, where Simon (Klein) spends winter days travelling up and down the slopes, grabbing whatever isn't locked down, then selling the stolen goggles, gloves and even skis to help support his sister Louise (Seydoux). They live in a tiny flat, but Louise is annoyed that she has to take care of Simon, and she's usually off with yet another boyfriend. So Simon begins to turn to other people for a sense of family, including a ski-lift chef (Compston) who helps him with his scam and a foreign woman (Anderson) who seems like the ideal mother.

In their scenes together, Klein and Seydoux have a remarkably authentic chemistry that includes tiny jealousies, rivalries, private jokes and a fierce loyalty to each other. As we learn more about their past, this takes on new meaning that's both warmly touching and darkly chilling at the same time. These two may have a difficult life, but they're enjoying it as much as they can. And their complicated relationship is packed with moments of tenderness that undercut the resentment.

The film is shot in an off-handed way that pulls us into each scene. The great cinematographer Agnes Godard captures the staggering beauty of the Alps along with tellingly intimate moments, contrasting their grim block of flats with the soaring natural scenery. And while some of the side characters feel a little contrived, they help us understand Louise and Simon in ways that catch us aback. This is a raw, unusually sensitive portrait of two people whose personal connection drives them crazy even as it gives them hope.

Rich Cline