An underdog wild card at the Oscars this year, Frozen River represents one of the best examples of the new trend for austerity and social realism in American indie cinema. That might sound worthy to the point of torpor, but this study of desperation and acute poverty is as tightly wound as a thriller. Melissa Leo dominates the film as Ray, a careworn mother of two, whose errant husband has stolen the money that was to have bought the family a new trailer. At her wits’ end and as fierce as a cornered mountain lioness when it comes to protecting what’s left of her family, Ray decides to smuggle illegal immigrants into the US across the treacherous ice of the Saint Lawrence River. It’s a lucrative operation, but one that is fraught with peril. Each time she makes the drive, the ice is thinner. Cracks ring out like gunshots under her wheels. Time is running out.

In this debut, the writer and director Courtney Hunt overdoes the symbolism occasionally — Ray’s elder son literally plays with fire at one point — but she builds an almost unbearable tension, which looms over Ray’s precarious plans for a better life like a gathering storm.

15, 97 mins

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