Is it real or is it myth? Or is it mytho-realism? Or possibly, reality-mythos? Or maybe it's just a movie.

That's Andre Techine's "Strayed," which initially seems to take place in a real world, then wafts off into an unreal one where extremely primal needs are examined, then returns to this one.

The time is 1940 and the Germans are moving across France to Paris where, everyone assumes, rape, pillage and killing will follow. Thus much of the population is on the run, including the beautiful widow Odile (Emmanuelle Beart, one of the world's truly stunning women) and her two kids, Philippe (Gregoire Leprince-Ringuet) and Cathy (Clemence Meyer). Somewhere to the south of the City of Light, the German fighter planes catch them on the road, and the result is a fast immersion in the horrors of modern war.

The car blasted, the refugee column shot to hell and gone, the dead and dying everywhere, Odile and her kids flee wildly into the woods. We're not sure where their savior comes from, but come he does -- he's just there, with them, giving orders, and never has a savior looked less like a savior. Yvan (Gaspard Ulliel) is about 17, a scrawny rat of a boy, in clothes too big, a hat that swallows his nearly-shaven skull. But something about him communicates one essential skill: He knows what to do next.

He guides them through the woods, though he's clearly of a class so far beneath their petit-bourgeoisie gentility they would never have registered his existence before. Soon enough, the family and their new best friend discover a hastily abandoned estate and, unsure what to do until the battle situation clarifies, set up housekeeping there.

It's almost, but not quite, a desert island. It's almost, but not quite, an idyll. It's almost, but not quite, civilized. But it sure is comfy.

How quickly these people fall into a kind of domestic rigidity. What is at stake, however, is the role of Yvan: Is he the new eldest son or is he the new husband? You can guess which one he prefers.

That's the movie: four people isolated in chaos, struggling to coexist, struggling to deal with each other's needs while not overlooking their own. Odile must establish certain rules with a mom's petulance, and she regulates the housekeeping. She also steals Yvan's gun, because she doesn't trust him, quite. Meanwhile, Yvan is in charge of hunting and gathering (he loots abandoned chicken coops, traps hares, fishes) and poor Philippe, a city boy, tries to stay with him; he admires the capable if low-class stranger but is also scared of him.

Director Techine is a master at drawing out the subtle tension in this awkward family construct, as each person struggles for leverage and power but understands that he or she cannot dominate, for to do so would be to crush the fragility of the arrangement.

"Strayed" calls to mind other desert-island films, such as "Lord of the Flies," where "civilized" boys devolve to a state of nature, or "The Admirable Crichton," where the butler proves to be the natural nobleman and comes to rule his aristocratic employers. Except that the subtext here, unlike in those two instances, is sexual.

You can feel Yvan's longing for the beautiful Odile, and she's not impervious to his allure. After all, in this cocoon of safety, he's the one who announces, "Honey, I'm home" every afternoon at 5, with a dead animal slung over his shoulder.

Of course it has to end. The sense of tenuous enchantment is finally overcome by history, first when two fleeing soldiers arrive and then with the coming of the local gendarmerie.

But "Strayed" has the strange clarity of a fable. It strips everything away until only instincts and emotions are left.

Strayed (95 minutes, at Landmark's E Street Cinema) is rated R for sexuality and violence.

Emmanuelle Beart as Odile, left, Clemence Meyer as Cathy and Gaspard Ulliel as Yvan flee the Nazis and find their way to safety of a sort in "Strayed."