One of the great pleasures of being a young moviegoer is sifting through the boundless treasure of movies that were made long ago, perhaps before you were born, pictures that have found a fresh audience year after year, decade after decade. The problem is that whenever you find something that particularly excites you -- it could be "Breathless" or "The Rules of the Game" or "The Bicycle Thief" -- there's always some smarty-pants type around who's eager to remind you that he or she got to it first: "Oh, I saw that 20 years ago, when I was in college," these people say, as if to grab credit for having made some grand discovery. That been-there, done-that spiel, aside from being purely annoying, makes it seem as if there are no "new" classics to discover. Everything great has been seen by someone, somewhere, before.

Then again, maybe not. Jean-Pierre Melville's "Army of Shadows," the story of a group of men (and one woman) working for the French resistance, was released in France in 1969. It received a lukewarm critical reception there, and was never released in the United States. Even American moviegoers who know Melville's other pictures -- like the somber-elegant 1970 gangster film "Le Cercle Rouge" or the brilliant 1967 end-of-an-era, end-of-a-man noir "Le Samourai" -- may barely be aware of its existence.

So in a way, "Army of Shadows" ("L'armée des ombres") is new to older moviegoers and younger ones alike, a chance for everyone to enjoy the unearthing of a lost masterpiece together. "Army of Shadows" is not just one of the great films of the '60s but one of the great films, period -- and the chance to discover it at the beginning of the 21st century, in an era when we think we've seen it all, is an unquantifiable privilege. The picture is being released in a restored version by Rialto Pictures; it makes its U.S. theatrical premiere this week at Film Forum, in New York, with dates in other cities to follow. (And those who don't get to see it in a theater will want to keep an eye out for its eventual release on DVD.) The fact that "Army of Shadows" is surfacing now may be proof that the god of movies works in mysterious ways: In an age, and a country, in which the word patriotism has been co-opted, corrupted and damned, Melville's mournful but vital study of what it means to love your country -- in all its wretchedness -- is just what we need.

"Army of Shadows" is based mostly on Joseph Kessel's 1943 novel of the same name, but Melville, active in the French resistance himself, also incorporated some of his own experiences -- or, perhaps more accurately, imbued the picture with dusky tones of melancholy that could only have come from personal experience. The picture opens with a quote from French novelist Georges Courteline: "Bad memories! I welcome you anyway. You are my long-lost youth." And throughout the movie, you can practically see these memories fluttering in from all corners, like spectral birds settling on a bare tree.

Lino Ventura (the European movie star who appeared in Louis Malle's "Elevator to the Gallows," also rereleased by Rialto last year, and who worked with directors like Claude Sautet and Jacques Becker) plays Philippe Gerbier, an engineer who is interned in a Vichy prison camp at the beginning of the movie. (The officer who signs him in flatters him by assuring him that, since it was originally designed for German officers, this is one of the better camps.) Gerbier escapes, although to call what happens an "escape" is both an oversimplification and an understatement -- the sequence in which Gerbier gains his freedom is deceptively lulling at first, before turning a sharp corner into quiet, shocking brutality.

Out on the street, he dips into a Parisian barbershop. The barber (he's played by the wonderful Serge Reggiani) may be friend or foe -- he has a pro-Pétain poster prominently displayed in the shop. In a sequence of astonishing intensity and simplicity, he gives Gerbier a shave, and the risk here isn't just that his razor grazes threateningly close to Gerbier's throat, but that he's able to scrutinize Gerbier's features. Gerbier waits to see what will happen. (Most of his work, as one sees later in the picture, consists of watching and waiting.) Finally, just as he's sending Gerbier out the door, the barber hands him a different coat to wear and a bit of money. The exchange is nearly wordless, but it tells us exactly where we are: in the middle of a war-within-a-war that needs to be fought largely with silent signals.

Even at this point, we don't yet know exactly who, or what, Gerbier is, but Ventura's sheer physicality gives us clues: His body moves with lumbering grace; there's both mystery and dignity in his musculature. As Ventura plays him, Gerbier is never an easy character to grasp: His tough boxer's mug is defined by a nose that's too big even for his large face; his eyebrows cut off our questions before we can even ask them. We need to watch him carefully to discern what he's thinking and feeling, but by the end of "Army of Shadows," we feel we've carried only a small portion of his emotional burden, and the weight is devastating.

Gerbier is, of course, a spy, and his circle of compatriots includes a young recruit in the fight to free France, Jean-François (Jean-Pierre Cassel), and a writer-philosopher named Luc Jardie (Paul Meurisse), the head of the entire network. (These two men are crucial to one of the movie's stunningly subtle twists.) Another colleague is mistress of disguise Mathilde (Simone Signoret, in a performance that's both elegant and earthy), a woman who might be a convincing seductress one minute and an undistinguished housewife running errands the next.

The action in "Army of Shadows" is both thrilling and subterranean: There's something going on every second, and yet much of that action is embedded in signals that the characters pass to one another with their eyes, the set of their shoulders, their tone of voice. The filmmaking is meticulous and deliberate but never poky. Melville uses many of the same techniques he put to use so effectively in his great gangster pictures, like the 1955 "Bob Le Flambeur" -- he keeps us alert, for example, by giving us crucial bits of information before we even know how to process them -- and the result is a picture that's both moodily evocative and as cutting as razor wire.

The movie opens with the vision of German soldiers marching along the Champs-Elysées with the Arc de Triomphe standing by, a single unblinking eye tracking the whole sorry scene. That same eye stands as witness over the movie's despondent, anguished conclusion. And in between, Melville packs a landscape of desolation: In this France (the movie takes place largely in Marseille and Paris), the streets are virtually empty, as if Gerbier and his mates were the last souls remaining on earth. Their flesh-and-blood enemies -- the Gestapo, Germany, their own government -- are certainly present, but the emptiness around them is the greater enemy. Melville captures that sense of isolation visually: His heroes can save their own country only by cutting themselves apart from it. "Army of Shadows" is in color (the lovely restoration for this rerelease was supervised by the movie's cinematographer, Pierre Lhomme), but they're lonely, heartsick colors, a palette of grays and greens and smoky blues that reconfigure themselves in the memory as black-and-white.

Melville's intention, I think, is to impart the gravity of Gerbier's mission -- to underscore his conviction that his country is worth saving -- by showing in unflinching detail the horrors that Gerbier and his colleagues need to surmount without even blinking: In "Army of Shadows," the killing of traitors isn't gleeful but intensely sorrowful. When Gerbier and his colleagues kill the young man whose betrayal led to Gerbier's capture, Melville doesn't fixate on the act of strangulation; instead he shows us the exact moment life leaves the young man's body, a decidedly nongraphic brand of violence that's far more disturbing than the explicit kind. Later, Jean-François allows himself to be arrested so he can help another prisoner escape. When he realizes that his colleague has been tortured past the point of survival (to the end refusing to give information to the enemy), Jean-François offers the man the single cyanide pill he possesses -- which means that when it comes time for his own torture, he'll simply have to suffer until he dies.

When it was first released in France, "Army of Shadows" did reasonably well at the box office. But particularly for a director like Melville -- who was revered by the new-wave directors -- the critical reception was disappointing. Cahiers du cinéma, a film magazine, contemptuously called "Army of Shadows" "the first and greatest example of Gaullist film art." At the time, Charles de Gaulle, who had been credited with delivering the country from the spontaneous uprising of May 1968, represented everything French youth hated about "old" France, and to them Melville's movie was steeped in the sentimental mythology surrounding the French resistance -- much of that phony revisionist boasting that, understandably, they wanted no part of.

But Melville himself, in a 1971 interview, noted, "Don't forget that there are more people who didn't work for the Resistance than people who did" -- apparently, he was as aware as his young detractors were that many of the older generation had greatly exaggerated their involvement in the fight to free France. And without using anything so blatant as actual words, he says as much in "Army of Shadows": The isolation of these freedom fighters, the way they seem to be the only people -- or the only Frenchmen -- left in the country is so palpable that, seeing this movie more than 30 years later, you wonder how the Cahiers naysayers could have missed it.

They were writing, of course, in the wake of May '68, and there were good reasons why they felt the need to look forward and not back. Even so, they blatantly misread "Army of Shadows." What does it mean to love your country so much that you'd swallow a cyanide pill for it, even as your own government is happily running it into the ground? Melville maps the true nature of patriotism, and even though wartime France is hardly analogous to contemporary America, his conclusions are painful to bear. The very concept of patriotism in early 21st century America is often derided as though it were nothing more than a collection of our worst impulses: The right to wave a flag, to bully other countries, to drive gas guzzlers, to bear arms, to decide what our children do (or don't) learn about sex or God or evolution in our schools.

"United we stand" may be the rallying cry, but the truth is that the love of one's country is too delicate a thing to be summed up by any single slogan or symbol. That's something Melville -- who died in 1973, at age 55 -- instinctively understood about patriotism: The very thing that we need to hold us together is actually the loneliest game in town.