Wes Anderson sweats the details. All of them, all the time, to an extent that can be maddening. But not in "The Grand Budapest Hotel," where the writer-director's familiar style blends with a group of unexpected factors to create a magnificently cockeyed entertainment.

With credits including "Moonrise Kingdom," "The Darjeeling Limited" and the stop-motion animation "Fantastic Mr. Fox," Anderson works so assiduously to create obsessively detailed on-screen worlds that the effect has sometimes been hermetic, even stifling. "The Grand Budapest," however, is anything but.

Delighting in all manner of old movie tropes, from elaborate chases to hairs-breadth escapes to Victorian plot devices like "the second copy of the second will," this playful yet poignant film, anchored by a knockout performance by Ralph Fiennes, tells the Boys' Own Adventure yarn of how a celebrated hotel concierge and a lowly lobby boy team up to have the adventure of a lifetime.

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It's not that Anderson, working with his usual team, including cinematographer Robert Yeoman, production designer Adam Stockhausen and costume designer Milena Canonero, has let up on the specifics here. Quite the contrary.

Even the smallest concrete yet imaginary element of "Grand Budapest's" main setting — the celebrated spa hotel in the fictional European republic of Zubrowka — was fanatically created by Anderson and company, down to its newspaper of record, the Trans-Alpine Yodel, and its pastry of choice, the mouthwatering Courtesan au chocolat, always packaged in the unmistakable pink boxes from Mendl's Patisserie.

Initially setting this fiercely eccentric world — Anderson's own Magic Kingdom if you will, apart from the director's previous universes — are aspects that combine to give it unexpected substance and more than a trace of sorrow.

For one thing, "Grand Budapest" is set in the past, not the present day, and, moreover, in a past that the film understands is overshadowed by darkness. It's a Central European world that's doomed to be destroyed twice over, first by storm trooper fascism and then by communism, and many of its people are not fated to survive the transitions.

Also elevating "Grand Budapest" is the transformative work of Fiennes as the film's protagonist, Gustave H, the concierge's concierge. Anderson has worked with fine actors before, but he's frankly never had someone so capable of giving his will-o'-the-wisp world heft and reality while still being faithful to the singular spirit that underlies it.

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Fiennes, last seen as the ebullient Charles Dickens in "The Invisible Woman," throws himself into the Gustave H role with unbounded but carefully calibrated zeal. Imperious, subservient and resplendent in an outlandish purple morning coat, he is the Grand Budapest's irreplaceable man, simultaneously in total charge and at your service.

Because of the way he's written by Anderson (who shares story credit with Hugo Guinness) and played by Fiennes, Gustave H is also a man of convincing feelings. That means his relationship with earnest lobby boy Zero Moustafa (a fine Tony Revolori), which starts as a master-protégé bond and becomes a real friendship, has an emotional genuineness that is rare in Anderson's films.

Before we meet Zero, or even Gustave H, the ever-indirect Anderson leads us, in classic oddball fashion, through a series of flashbacks that cover and protect the main story like a group of Russian nesting dolls.

We start briefly in the present day, in a cemetery in Zubrowka's capital city of Lutz, with a tribute being paid to the country's most celebrated writer, the beloved author of a novel called "The Grand Budapest Hotel."

Then we go back to 1985, and listen as that author (Tom Wilkinson) gives a radio talk about how he came to write the book. Then we go back yet again to 1968, with the still-unnamed author (now played by Jude Law) taking his ease in the Sovietized Grand Budapest, an almost-derelict hotel with a palpable air of sadness about it.

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It is here that the author meets the adult Zero Moustafa (F. Murray Abraham), now the richest man in Zubrowka and the owner of the Grand Budapest. How, the author wonders, did he come to buy it? Over an elaborate dinner, the film flashes back to 1932 and settles down to tell its main tale.

Gustave H, it turns out, is not only the concierge of the Grand Budapest but also the main reason many visitors come in the first place. This is especially true of a group of elderly female guests of substantial income who rely on this most accommodating of men for the romantic/sexual services he is always willing to provide.

First among equals is the fabulously wealthy 84-year-old dowager countess Madame Celine Villeneuve Desgoffe und Taxis, familiarly known as Madame D. (Yes, that's Tilda Swinton under five hours of daily makeup and a Bride of Frankenstein wig).

The most unimportant person at the Grand Budapest is Zero, provisionally hired as a junior lobby boy in training. Belying his name, Zero sees everything and becomes the last living witness to an era where service and politeness were everything and rudeness was considered to be no more than "the expression of fear."