Available on DVD: “Shame”

Brandon (Michael Fassbender) wants sex. It’s all he thinks about, 24/7. At work, at play, at home, on the subway, in the street and especially in the bedroom. It doesn’t matter what time of day it is, or where it is, or with whom it is. He has to have it.

That makes him difficult to live with. Just ask his sister Sissy (Carey Mulligan). Brandon doesn’t want her in his apartment and can’t wait until she leaves. She argues that, as family, they should be there for each other. He strongly disagrees. It’s hard to imagine more incompatible siblings.

But in Brandon’s defense, Sissy is seriously unstable. Singing New York, New York in a trendy nightclub, she sounds as if she’s on the precipice of a psychotic break.

Shame is a complex, challenging, emotionally devastating drama from one of the most exciting filmmaking collaborations to emerge in the past decade: Fassbender and director Steve McQueen. McQueen, working from a screenplay that he co-wrote with Abi Morgan (The Iron Lady), takes much the same bare-bones narrative approach that worked so well in Hunger (2008).

But as with that film, Fassbender’s contribution is essential. In McQueen’s hands, he’s not so much a blank slate as he is a reflecting pool, tapping into Brandon’s disturbing blend of self-absorption and self-hatred. His alienation, it’s implied, could be possible only in a world in which the more people turn to devices that supposedly connect them, the more deeply they sink into despair.

Shame is not for everyone; that NC-17 rating isn’t just a design element. The film is a raw, unsparing look at the downside of humanity. Some critics have complained that it doesn’t address the reasons for Brandon’s behavior, but it doesn’t have to.

To paraphrase a character in Michael Clayton, people are incomprehensible.