Brandon, the tightly wrapped Manhattan businessman played by Michael Fassbender in Steve McQueen's Shame, is a puzzle missing a few pieces, mostly around the heart.

Brandon and his unstrung sibling, Sissy (Carey Mulligan), are the central figures in McQueen's unrelenting and intensely compelling film. The brother's sexual compulsion and the sister's emotional neediness offer clues to a family trauma that consumes them. During the film I began to imagine them as Hansel and Gretel trying to elude the witch who wants to eat them.

He uses sex (Internet pornography, hookers, pickups) to armor himself from intimacy. She uses it as a means of getting close to another, however briefly.

In this NC-17 film, there is much nudity and much more graphic sex. It serves to make the audience as alienated and lost as its characters. It also serves as a constant reminder of those who can bare flesh but not their souls.

In his double portrait of the unconsummated frenzy for pleasure and human connection, McQueen has three formidable tools to command the audience's attention. One is Fassbender, inscrutable for much of the film, a wizard of id and sexual flypaper for women except those he actually cares about. Two is Mulligan, her English-rose dewiness made pasty and prickly, her dimples the last vestiges of allure.

The third is a lost instrument of the filmmaker's art: The long take. While the sex scenes are products of frenetic editing, the emotional sequences in Shame are shot in sustained real time and are so in-your-face that I felt like a personal-space invader overwhelmed by Brandon's palpable repression of feeling and Sissy's almost narcotized expression of it. (Watch her sing, in extreme close-up, the anthemic "New York, New York" as though it were a dirge. Watch his face when his boss explains that his computer has been seized because it's "filthy." Gives a whole new meaning to "hard drive.")

Around the time Steven Soderbergh made Full Frontal, he observed that once an actor took his clothes off in front of the camera, the movie became a documentary. Shame, which McQueen cowrote with Abi Morgan (scribe of the forthcoming Maggie Thatcher biopic, The Iron Lady), is an exception to the Soderbergh rule.

With McQueen, the sex is a frantic montage of action without sensation. With McQueen, the long-take conversations between characters (such as the eight-minute sequence between Fassbender's Brandon and Nicole Beharie's Marianne, the coworker he asks out for dinner) have the halting inarticulateness of unscripted characters in a documentary.

Who is the audience for this aggressively unsexy movie about a man who engages in empty sex and feels numb? About a woman so hungry for love that a look can bruise her? Pretty much anyone who has unresolved family issues, which includes a significant part of the population old enough to see it. McQueen finds the exquisite tension between the brother wanting to disconnect and the sister longing for connection. To paraphrase a line of Sissy's, it's a good movie that comes from a bad place.