AN ISRAELI MOVIE WHOSE CHARACTERS ARE MOSTLY ARABS, Ajami is a cleverly constructed and smartly realized crime thriller that barrels — or rather, twists — right past politics. Named for a mixed but mostly Arab neighborhood in Jaffa, the movie doesn't ignore the Israeli-Palestinian divide. (How could it?) But this collaboration between Arab and Jewish writer-directors — Scandar Copti and Yaron Shani, respectively — concentrates on intimate details of tribal conflict, paying little mind to larger geopolitical issues.

The film is divided into five chapters, and Israeli characters don't even arrive in the first one. Not that harmony prevails until then. The story begins with a drive-by shooting, its innocent victim mistakenly killed by members of a Bedouin gang feuding with an Arab family. Later, the filmmakers introduce another conflict that has nothing to do with Jews: It's between a Muslim Arab and a Christian one. As for the major Jewish character, he's trouble for the others mostly because he's a cop.

The opening sequence is narrated (and drawn) by 13-year-old Nasri (Fouad Habash), a budding cartoonist. The subsequent episodes are jumbled chronologically, but eventually circle back to Nasri. The tale pivots, however, on Nasri's older brother Omar (Shahir Kabaha), who at 19 is his family's "elder." That forces upon him the responsibility for raising the equivalent of $57,000, the amount an imam calculates as the price for ending his clan's beef with the Bedouins. Just the near-documentary scene in which this judgment is delivered is worth the foreign-film Oscar for which Ajami has been nominated.

To earn some of the money, Omar takes a job at a beachfront café owned by the neighborhood fixer, Abu Elias (Youssef Sahwani). Another new employee is Malek (Ibrahim Frege), an undocumented Palestinian who sneaked across the border from the West Bank; he's trying to accumulate cash for his mother's bone-marrow transplant. The cook (played by co-director Copti) is Binj, an easygoing, goateed Arab with a Jewish girlfriend. (Binj is one of more assimilated Arabs, who can be spotted by their ability to speak Hebrew.) The cafeé's hostess is Elias's pretty daughter, Hadir (Ranin Karim); she and Omar fall in love, but her prosperous Christian father would never let his daughter marry an penniless Muslim.

Tensions spiral because of two more deaths: A Jewish Ajami resident is stabbed after he complains about the noises made by the sheep kept by some Arab neighbors, and the body of a possibly AWOL Israeli Army man (who may not have been murdered) is found in a West Bank cave. The soldier's older brother is gentle family man and brutal plainclothes detective Dando (Eran Naim), who goes on a rampage in Ajami after the corpse turns up. Dando and two cohorts raid Binj's apartment, inadvertently setting in a motion a series of events that will lead to several more fatalities. The circle is completed in a movie that insists on both unruly reality and meticulous narrative.

The tidy structure is the film's principal difficulty. Unlike the thematically related but more persuasive City of God, which attempted a similar balance of chaos and order, Ajami doesn't present itself as communal myth: If City of God seemed excessively neat, it was because it was a collection of gangster legends, already well chewed by the residents of Rio's favelas. Ajami doesn't have that dimension; it's merely a flashy storytelling exercise, deepened by its ethnic-strife context.

But the movie's evocation of contemporary Israel's many divisions is no small accomplishment. Copti and Shani cast non-professional locals, and shot on real locations with handheld camera. Those aren't new gambits, but they're dependable ones, so long as the filmmakers (and actors) work with honesty and passion. Neither quality is lacking here. Unlike Shutter Island — another convoluted tale named for its powder-keg location — Ajami uses fiction in the pursuit of real understanding, not just cheap effect.

AJAMI — 2009, 120 min; at the Avalon Theater.

PERHAPS MARTIN SCORSESE SHOULD TAKE A FEW YEARS OFF from movies. Not from making them — from watching them. His new Shutter Island is just the latest in a string of genre exercises, over-inflated remakes, and movie-movie indulgences.

The director's previous fiction feature, The Departed, was his liveliest since 1999's Bringing Out the Dead. But it only seemed fresh because it borrowed from Hong Kong rather than Hollywood. With his latest, Scorsese returns to familiar film-buff turf, using massive resources and a prestige cast to make a 1950s-style B-movie. Sam Fuller never had it so good, but then he never made a picture — Scorsese's preferred term — as pointless as Shutter Island.

Derived from a novel by Dennis (Mystic River) Lehane, Shutter Island is set in 1954, primarily on a slab of rock in Boston harbor that's home to an asylum for the criminally insane. As a massive storm looms, grim-faced U.S. marshal Teddy Daniels (Scorsese "muse" Leonard DiCaprio) and his brand-new partner (Mark Ruffalo) arrive by ferry to investigate the escape of a woman who killed her three children. Teddy is cocky, worldly, and pragmatic. He has no patience for the psychological cleverness of the institution's top psychiatrists (Ben Kingsley and Max von Sydow), and rapidly becomes convinced that someone — or perhaps everyone — is hiding information from him.

Although Teddy comes on like a regular guy — never DiCaprio's strength — we soon learn that he has some irregular memories. The G-man's wife (Michelle Williams) was killed in a fire, and she still appears to him in color-saturated visions, sometimes turning to blood and ash as he watches helplessly. The music of Mahler, played on a phonograph in the head shrinks's absurdly ornate parlor, transports Teddy back to World War II, when he was one of the U.S. soldiers who liberated Dachau.

Or so he says. But Dachau, which was not an extermination camp, here looks more like Auschwitz, complete with mounds of bodies on the ground and the infamous "Arbeit Macht Frei" sign over the gate. (Dachau had the same motto, but a different sort of sign.) And the piled corpses are frozen and icy, even though American troops first entered Dachau in late April. So we know (if we know a little World War II history) that the flashbacks are false. The question is, who's lying? Teddy, or his creators? It takes a very long time to learn the answer, which is not particularly satisfying.

Since Shutter Island depends on a series of twists, summarizing the plot further would be a disservice to potential viewers. The movie is little but plot, aside from its high-production-value attempt to simulate low-production-value fare like Fuller's Shock Corridor. (Scorsese even enlists the discordant music of such 20th-century composers as Ligeti, Penderecki, and Cage, instead of the knock-offs that a '50s production would have used.) It could be argued that the film — with its references to Nazi horrors, the House Un-American Activities Committee, and Manchurian Candidate-style brainwashing experiments — is political. But it doesn't actually have anything to say about the Cold War era's ideological climate. Shutter Island isn't even nostalgic for mid-'50s paranoia — just for the cheap scare flicks that the period's anxiety inspired.

SHUTTER ISLAND — 2010, 138 min; at the Uptown and all the usual multiplexes.