If you want to get into the movies, Steve McQueen is a hell of good name to go by. But Steve (Bullitt) McQueen wouldn't have been a good fit in the films of his latter-day namesake. This McQueen is a Turner Prize-winning artist whose Hunger, a study of the fatal 1981 hunger strike by IRA prisoner Bobby Sands, won Cannes' first-feature prize in 2009 and was possibly the best movie that no one saw that year.
Shame has more in common with Hunger than the single abstract-noun title and the man in the starring role: it's a portrait of a man on the edge, which is profoundly confronting because it is so coolly clinical. It's a film about an addict but, until a mesmerising and almost transcendent climax, it is played so low-key that it's almost affectless: the film's full horror consists in the banality of its main character's obsessive behaviour.
The man in question is Brandon (the extraordinary Fassbender) and his addiction is to sex. He works in an unspecified high-tech office (where his computer's hard drive collapses under the weight of the porn he's downloaded) and plays - well, just about anywhere he can find a playmate, though it's quickly plain he will vigorously make do in the absence of a partner.
In two early and crucial scenes - encounters on the subway and in a bar - Fassbender conveys with ineffable subtlety the mixture of irresistibly cool charm and self-loathing that drives Brandon's ceaseless predatory behaviour. It could go on for ever, but the arrival of his sister Sissy (Mulligan), a wannabe crooner with demons of her own, changes everything. The relationship between these two plays out in tempestuous fashion as their separate, desperate needs collide. We learn nothing about what has made them the way they are - the only hint is a voicemail in which Sissy sobs that "we're not bad people; we just come from a bad place" - and the catharsis that arrives is far from redemptive: McQueen is concerned just to depict and observe, and not to process, the unbearable heaviness of his characters' being.
This makes the film sounds forbidding, which it's not, though its certainly a challenging watch. Like Hunger, Shame tells its story in a series of eerily handsome single-shot set pieces, in which style trumps naturalism. When Sissy, singing a frail and trembling New York, New York, stuns a bar into silence, it may seem narratively implausible, but it's profoundly revealing: these characters exist not in a social landscape - the depopulated Manhattan in which they move underlines their isolation - but in the wasteland of their unquenchable sorrow.
Cast: Michael Fassbender, Carey Mulligan
Director: Steve McQueen
Running time: 101 mins
Rating: R18 (sex scenes, suicide)
Verdict: When sex goes bad