A British single-seat Spitfire glides in near silence along the beaches of Dunkirk, France, no more than a hundred feet above the dull-colored sand and the bright, azure waters.

The Royal Air Force pilot has run out of fuel, and he has run out of options. Even if he manages to complete a successful landing on the beach, his fate is sealed.

This is but one brief moment in Christopher Nolan’s “Dunkirk — but the beautiful and mournful and breathtaking visual of that lone plane outlined against the sky and the sand and the water is so powerful and so indelible, if I close my eyes, I can see it as clearly as when it appeared on the big screen.

“Dunkirk” is filled with such unforgettable scenes — some epic in scope, filmed in deep long shots, others so intimate and claustrophobic we have to remember to take a breath. It is a great film about one of the most pivotal battles in World War II, in which the ultimate goal of the heroes was not to emerge victorious but to somehow find a way to retreat in order to regroup and fight another day.

The events in “Dunkirk” take place some 18 months before the bombing of Pearl Harbor plunged the United States into World War II, but many historians say if things had gone differently on those beaches in May and June of 1940, Europe would have been overrun by the Nazis.

Writer/director Nolan has built his enormously successful career trafficking in the time-bending and the fantastical (“Memento,” “Inception,” the “Dark Knight” trilogy), but with “Dunkirk” he delivers a faithful and deeply respectful re-telling of history — albeit while zig-zagging along the timeline and showing the same event from multiple viewpoints. It makes for an enthralling if at times slightly confusing work that demands (and commands) our undivided attention.

The opening sequence has the pace and the feel of the third act of many a war film — and in fact the entire movie feels like a final act. There’s very little exposition, almost no backstory. Everything is focused on the situation at hand. (With a running time of 1 hour and 47 minutes, “Dunkirk” is much shorter than most of Nolan’s films.)

Nearly 400,000 total Allied troops, most of them French and British, have been penned in by the Germans — but we follow just a small band of troops, and then just one soldier, a callow Brit named Tommy (Fionn Whitehead in a strong everyman performance), as he scrambles over fences, dashes down abandoned streets and dives for cover while bullets rain all about.

When Tommy finally stumbles onto the Mole — an extended jetty at the outer harbor of Dunkirk — he is met with an overwhelming and almost surreal tableau: thousands of Allied troops standing in long, parallel lines, facing the English Channel. They don’t even bother with their weapons, because their rifles are useless at this point.

The Channel is the only means of escape — but the waters are too shallow for larger British Navy vessels to pick up the men, and Luftwaffe planes are periodically buzzing overhead, dropping bombs on troops that are sitting ducks. It seems to be an untenable situation sure to result in thousands upon thousands of Allied casualties.

In England, the call goes out for civilian boats of all manner and size to come to the aid of their countrymen — and literally hundreds of motor boats, steamers, barges, private yachts and fishing boats set out for Dunkirk, to retrieve the troops and bring them all the way home or to Navy ships awaiting off the coast.

With Hans Zimmer’s pounding, electrifying score and some perfectly timed and sometimes jarring editing choices ramping up the tension, “Dunkirk” weaves multiple storylines, as we experience the massive evacuation effort from the perspective of a number of angles, including:

— A quietly determined, middle-aged civilian boat captain (Mark Rylance in a brilliant performance) who says men his age create these wars — so the least he can do is try to save some of the young men whose lives are in peril.

— A noble British Naval commander (Kenneth Branagh, excellent as always) who takes on the nearly impossible mission of evacuating tens of thousands of Allied troops. The commander wistfully notes one can practically see home from Dunkirk, and yet it might as well be a thousand miles away.

— Two RAF pilots (Jack Lowden and Tom Hardy) engaging in one dogfight after another with the enemy, sometimes just a few hundred feet above the water.

— A shell-shocked British soldier (Cillian Murphy) whose mere presence on a civilian boat puts the captain and his crew of two teenage boys in peril.

— A group of soldiers hunkered in the hull of a boat sitting in the sand at the edge of the water, waiting for the tide to come in as they sustain enemy fire and deal with a possible traitor in their midst.

Nearly every scene in “Dunkirk” brings about another moment of crisis, another opportunity for heroics, another instance of young soldiers and their commanding officers scrambling to evacuate while facing peril at every turn.

This is an intense but not especially violent film. Nolan opted for a PG-13 rating and eschewed graphic scenes of bloodshed in favor of focusing on the emotional, psychological and spiritual challenges facing these young soldiers.

Fine work from the cast, from veterans such as Rylance and Murphy and Hardy and Branagh, through newcomers such as Whitehead and the pop singer Harry Styles.

But the star of “Dunkirk” is the movie itself. Nolan has crafted a tight, gripping, deeply involving and unforgettable film that ranks among the best war movies of the decade.

‘Dunkirk’

★★★★

Warner Bros. presents a film written and directed by Christopher Nolan. Rated PG-13 (for intense war experience and some language). Running time: 106 minutes. Opens Friday at local theaters.