It’s a scenario as old as film itself: Heeding the call to glory, a country boy trades in his overalls for a uniform, leaves his sweetheart on the family farm, and marches off to war. His will to survive is tested at the front and the girl’s love and loyalty are tested at home. But in Bruno Dumont’s subdued, lyrical, and gruesomely violent new film, “Flanders,” which opens today, war and peace are each a distinct level of hell.

Barbe (Adélaïde Leroux), the girl for whom Demester (Samuel Boidin) pines, isn’t really his. “We’re just friends,” the hulking farm boy tells a guy giving Barbe the once over in the local bar. “We’ve known each other since we were kids. Her farm’s near mine.”

Grown into a lissome womanhood, Barbe uses sex to keep men physically close but emotionally distant. Though Demester occasionally receives the same benefits that the girl he so clearly adores freely dispenses elsewhere with little modesty, passion, or care, Barbe’s commitment-phobic ego and troubled soul won’t let her give her heart to him. Instead, on the eve of Demester’s departure for the field of honor, she beds Blondel (Henri Cretel), another fledgling warrior from Demester’s regiment.

Combat works its infernal magic on Demester and his comrades as they endure heat, flies, and house-to-house fighting in an unnamed desert war. Slowly sinking to the same amoral level, the men shoot first (and worse) and ask questions later. But Demester, Blondel, and their buddies are not the only ones who have lost their way. Back home in Flanders, the pressure of awaiting the hero’s return while carrying an unborn child belonging to one of them is too much for Barbe, and she snaps. It’s now not only a matter of whether Demester and Blondel will claim her if and when they return home, but what will be left of her to claim.

“I’m interested in genres,” Mr. Dumont said recently. “Stories that have this kind of mythic quality are always the same. What is different is the way that mythical story is expressed, rather than the story itself.”

On the heels of having his way with a coming-of-age film (1996’s “La Vie de Jesus”), a policier (1999’s “Humanite”), and a love story with suspense elements (2003’s “Twenty-nine Palms”), the 48-year-old Frenchman has now made a naturalistic micro-epic that speaks in a persuasive, hypnotic, and very disturbing narrative whisper. Cast with nonactors, performed with an absolute minimum of dialogue, and free of a manipulative musical score, “Flanders” may be the quietest combat movie ever made.

“I really am someone who believes in the hypnotic power of sound,” Mr. Dumont said. “The sound really deepens the understanding and the perception of the film. That’s one of the reasons why the actors in my films speak very little.” Rather than beefing up the mayhem with post-recorded sound effects, “when the men shoot, they are the actual sounds that are recorded at the moment,” Mr. Dumont said. “In a sense, this film is almost a war against the aesthetic big studio films where the sound is choreographed and is almost operatic.”

Though low-fi by Jerry Bruckheimer standards, the single-channel monophonic audio track in “Flanders” has a grimly enchanting lucidity. “For me, the sound becomes almost like music,” Mr. Dumont said. “It doesn’t serve as a commentary to the image, it becomes a part of the image.”

Like Mr. Dumont’s previous pictures, the images in “Flanders” are stunning. The densely detailed earth-toned fields and interiors of the contemporary Flemish countryside, and the arid moonscape of the faraway war (shot on the same Southern Tunisian locations that became Tatooine in “Star Wars”) possess a subtle but absolutely rock-solid compositional clarity. During the course of four features, Mr. Dumont has established himself as a filmmaker of compositional gifts outside the reach of most of his peers. “In all of my films, the landscapes are mental landscapes, they’re interior landscapes,” he said. “When Demester is fighting the war in the desert, what you’re really seeing is the war that’s going on inside of him. It’s the same for Barbe.”

With sparse, rarely explicative dialogue and no score, Mr. Dumont’s cast has to carry a considerable storytelling burden. But rather than rely on the techniques and assumptions of experienced performers, Mr. Dumont prefers to work with amateurs. “Most of the actors in ‘Flanders’ I found either in employment agencies or in court,” he said. In court? “Well, to play the soldiers I really was looking for bad guys and when you’re looking for bad guys, a good place to find them is in court.”

Ms. Leroux and Mr. Boidin inhabit their characters and the film’s harrowing circumstances with a peculiar, expressionless nobility. “It’s a combination of the real and the fictional,” Mr. Dumont said of his leads’ zero-affect charisma. “I gave them no screenplay and there were no rehearsals. What I really hope is that the character will develop naturally. That’s what I’m looking for, this truthfulness.”

Mr. Dumont’s process may be unorthodox, but he has evolved his methods organically. “I wanted to go to film school but I was thrown out,” he said. “So I studied philosophy instead.” After completing his philosophical studies, he secured a job making industrial films. The two disparate disciplines, philosopher and non-fiction filmmaker, turned out to be a perfect training ground for a series of radiant and brutally honest narrative features that have claimed the Cannes Jury Prize twice. “Making films in factories,” he said. “I really had to learn to make something that was uninteresting interesting.” And philosophy? “Philosophy taught me that the body is the cause of the spirit,” he said. “So I film bodies in order to show souls.”