"Traitor" is a movie about a gang of Islamist terrorists being hunted by U.S. intelligence agents. For reasons best known to themselves — fear of fatwa, perhaps — the filmmakers have chosen not to acknowledge this plain fact. Instead, their press notes speak airily of "a taut international thriller set in the treacherous world of covert counter-espionage operations." This is like describing "The Dark Knight" as an offbeat urban romance, and it prefigures the conceptual confusion to come.

Don Cheadle plays Samir Horn, a former U.S. Army special-ops sergeant who appears to have gone rogue — we first see him delivering several crates of Semtex detonators to a terrorist cell. Horn is a complex character, however: He spent his childhood in Sudan, the land of his father, who was blown up by terrorists before his son's eyes. After that, Horn was taken to Chicago, where he was raised by his American mother and grew up to be a devout Muslim.

FBI terrorist-buster Roy Clayton (Guy Pearce, sporting a Van Dyke beard and a soft Southern accent) and his partner, Max Archer (snarly Neal McDonough), are hot on Samir's trail. They almost manage to cart him off from a terrorist headquarters in Yemen, but he wriggles away. Continuing their investigation, they learn that Horn underwent terrorist training in Pakistan, that he appears to have been involved in a resort bombing in Spain that claimed the lives of several Americans, and that he has since moved on to Marseilles, where he and an idealistic fellow terrorist named Omar (soulful Saïd Taghmaoui) have hooked up with a cynical terror chief named Fareed (the superbly oily Aly Khan). Now they are plotting a series of attacks in America, where a squad of suicide bombers is already in place. Can Clayton and Archer nab Horn before he triggers a national calamity? And if they do, will they discover this mysterious renegade's true allegiance?

The best parts of the movie are a long prison interlude, which has a parched, dusty vérité, and several chase and combat sequences, which are convincingly chaotic. Pearce, always an inventive performer, has little to do here beyond deploying his elegant cheekbones; and Jeff Daniels, as a CIA weasel who is the key to an overarching conspiracy, barely has a character to work with. But Taghmaoui and Khan, both fine actors, bring illuminating detail to their portrayals of two very different Islamist warriors. And of course Cheadle — a master at conveying states of thought and feeling with the most minimal means — could probably hold our attention just sitting in a corner staring at his shoe.

Unfortunately, for extended stretches of this movie, that's pretty much what he's compelled to do. His Samir Horn is a man wracked by obscure inner torments involving oppression, rebellion and the true nature of Islam. These are unusually weighty issues for what is essentially an action thriller; but since we have no clear idea what's at stake for Samir until near the end of the picture, he seems for most of its length to be literally lost in thought, leaving us rudderless amid the gunfire and the globe-trotting.

Apart from the performers, and some atmospheric photography by J. Michael Muro, the movie is a conflicted muddle. A maddening amount of care has been taken to avoid giving offense — to explain at length that not all Muslims are terrorists (you don't say?) and that not all terrorists are bad guys (a harder sell, and one that probably wouldn't resonate with their victims — many of whom, of course, are other Muslims). So many punches are pulled in an effort to make us see all sides of every question that after a while, we begin to feel as if we're suffering through an endless ethics lecture by an especially windy professor.

This moral dithering leaves the picture becalmed on the screen — a crucial flaw in an action movie, even one that aspires to thoughtfulness. Since so much artistic effort has gone into making the film, you have to wonder who screwed it up. Was it the director, Jeffrey Nachmanoff, who wrote the screenplay from a story suggested by Steve Martin (yes, the veteran comic actor)? Or — more likely, perhaps — was it the movie's herd of 13 producers, whom one can imagine providing helpful second-guessing at every narrative turn? Whatever the case, the substantial issues the picture seeks to address are lost among the eggshells on which it attempts to walk.

Don't miss Kurt Loder's review of "Sukiyaki Western Django," also new in theaters this week.

Check out everything we've got on "Traitor."

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