Tim Blake Nelson's "The Grey Zone" strikes a bold, even courageous blow against the pious cliches of most Holocaust films. Jagged, unrelenting, claustrophobically intimate, it does more than any other in recent memory to avoid the platitudes and cheap sentimentality that, on film anyway, have come to represent the murder of 12 million people by the Nazis during World War II. If "The Grey Zone" ultimately succumbs to some of those cliches, it's due more to the exigencies of moviemaking than to Nelson's own admirable instincts as a director.

Set in Auschwitz in 1944, "The Grey Zone" has to do with the Sonderkommando, the "special squads" of Jews that Nazi officials forced to help with the processing of new arrivals to the camp and, later, with the disposal of their corpses. The Sonderkommando, as Primo Levi wrote in his memoir "The Drowned and the Saved," occupied a gray zone of moral reasoning: They agreed to carry out their unspeakable labors under threat of death, with the promise of a few more privileges (alcohol, cigarettes, better food) and a few more months to live. Were they traitors? Victims? More to the point, how can anyone presume to judge?

Nelson plunges the audience into the heart of that moral dilemma in "The Grey Zone," which he filmed using a hand-held camera in big, often disorienting close-ups. His ensemble of capable actors speak in American accents and vernacular, the better for American audiences to enter a world that is portrayed here with grisly, unsanitized realism. More than any other major feature film to date, "The Grey Zone" reproduces the filth and brutality of the camps (as Levi said, if they had existed any longer a new language would have had to be invented to capture their horrors), and the moral ambiguity of their denizens. Viewers will no doubt be confused at first, not sure of what they're seeing or hearing -- as apt a way as any to convey the terror and confusion of life and death in Auschwitz.

The plot of "The Grey Zone" has to do with the events of October 1944, when the 12th Sonderkommando unit staged an uprising at Crematorium 1. In rapid-fire dialogue and quick, often brutal scenes, Nelson sketches out the conflicts that threatened to scuttle the revolt, from sectarian differences between Hungarian and Polish Jews to competition and distrust within the group. This is a desperate and, in many cases, nasty group of men, all of whom have made a Faustian bargain, each of whom carries his guilt and shame in his own way.

At the center of the story is the Hungarian doctor Miklos Nyiszli (Allan Corduner), whose memoir served as a reference for Nelson in writing the script. Nyiszli was ordered by Josef Mengele to conduct postmortem experiments on sets of recently exterminated twins; here the drama revolves around Nyiszli's philosophical conversations with his superior, an SS officer named Muhsfeldt (Harvey Keitel). But the person who leads the audience through this circle of Hell is a fictional character named Hoffman, played by David Arquette in a performance that should put his reputation as a lightweight permanently to rest. Despondent, in an alcohol-induced haze, Hoffman is on the edge of something -- suicide, homicide, we don't know. But when he discovers a 15-year-old girl (Kamelia Grigorova) who has survived a gassing, he decides to save her, presumably atoning for his part in his brethren's deaths. He persuades his colleagues to hide her in an act that threatens to disrupt the uprising and get them all killed.

Nelson packs an enormous amount of information into "The Grey Zone" (an entire subplot takes place at a munitions factory, where four women, including two played by Mira Sorvino and Natasha Lyonne, smuggle dynamite to the Sonderkommando), which is its blessing and its curse. In his zeal to tell the story of the Sonderkommando and make it the vehicle for a much larger ethical conversation and push the limits of cinematic storytelling, Nelson creates a movie so complex as to be almost incomprehensible. But then again, why should the Holocaust be anything but incomprehensible?

"The Grey Zone" is at its best when it's in the bunker with the 12th Sonderkommando, especially as it observes the Mamet-like arguments between a Hungarian named Rosenthal (David Chandler) and a Pole named Abramowics (Steve Buscemi). But as the action becomes more heated and the girl (who actually existed but had no part in the 1944 uprising) appears on the scene, "The Grey Zone" begins to succumb to the very conventions it's trying to throw off. Worse, Keitel's "Ve heff vays uff mecking you talk" German accent is a jarring distraction in the midst of the movie's naturalism.

Still, Nelson gets some amazing performances from a terrific cast, especially Corduner and Chandler. And much of the writing is so good that it makes one long to see Nelson's 1996 play on which "The Grey Zone" was based, which doesn't seem to have benefited from being opened up here. When Nelson decided to make a movie, he bought into the movies' grammar of movie stars and bad accents and heightened action and ritualized violence and torture. No matter how true to original events -- or, more importantly, intellectually honest -- Nelson is in "The Grey Zone," the movie still exists as a spectacle, one that will be consumed along with previews and popcorn and all the accouterments of the multiplex.

Nelson tells an important story with "The Grey Zone," in what has become the chief storytelling medium of the age, but it might be that in doing so, he's made a deal with a different kind of devil altogether.

The Grey Zone (108 minutes, at the Cineplex Odeon Outer Circle and Shirlington, and Landmark Theatres Bethesda Row) is rated R for strong violence, nudity and language.

David Arquette as a member of the Sonderkommando, the "special squad" of concentration camp inmates coerced into collaboration with the Nazis. Below, Kamelia Grigorova and Allan Corduner.