What was originally pitched as a straight action flick - a sort of Middle Eastern Treasure of The Sierra Madre – becomes in the hands of sometime indie writer-director David O Russell the most subversive picture to escape a major studio since Warren Beatty's equally ambitious (and equally flawed) Bulworth.

Throughout read oil for gold and suddenly Russell's film begins to look a lot like the war being refought in microcosm. At least until Wahlberg is captured and tortured and the equation that by-passed so many watching at home on CNN - that oil and force equals money - is made explicit. Elsewhere, Clooney explains to his trigger-happy comrades not only the painful consequences of bullets but modern American methods of warfare that sanction the burial alive of hundreds of Iraqi troops in their desert trenches. The film stops short of laying bare the obscenity of the Basra road (still arguably the best kept open military secret of recent years), but it must have come as a hell of a slap in the face to the gung-ho complacency of more unwary US viewers. If the ending is a feel-good compromise, its journey is not.

But then little about Russell's picture plays it quite the way the only other major production about this dirty little war, Ed Zwick's flag-waving Courage Under Fire, would have it. Visually Russell juggles his stock, leaping from bleached newsreel to colour-soaked surrealism. He takes the camera inside Wahlberg's torso with his bullets, rigorously traces others from shooter to shot. His is not a film of mock heroics; Three Kings is an action movie with consequences.

Nor does it feel embarrassed to play equally fast and loose with both comedy (Jonze is particularly good) and humanity. How rare a Hollywood beast is the film that not only fails to take a clear moral line (only Saddam Hussein himself is seen as villainous), but that treats its Arab characters with as much respect as its stars? (French-Moroccan actor Said Taghmaoui, best known for La Haine, is superb.)

There are obvious flaws. One late set-piece falls for the bang-bang cliches, and the climax is soft-centered (if not soft-headed). But these are cracks rather than canyons, and it's hard not to love a film that calls upon a star like Clooney to voice an explicit criticism of George Bush's betrayal of the Iraqi opposition. Three Kings - brains as well as brawn.