Disappointments temper triumphs in this story of Nathan, a young maths genius on the autistic spectrum, but in a way that is ultimately the opposite of disappointing.

Too often, the cataclysmic end of civilization in fiction functions as merely a fantasy about a certain kind of freedom. But not in this film, whose dramatic vision is not one of shaking off, as it were, the oppressive yoke of parenthood, but of growing up and taking it on.