"The Return of the King" — the third and concluding installment of director Peter Jackson's unprecedentedly splendid "Lord of the Rings" trilogy — is a cavalcade of wonders. The movie is three hours and 20 minutes long and it flies by. There is virtually not one moment that doesn't pulse with grandeur, with thundering spectacle and epic emotion and stupefyingly beautiful visual inventions. Words almost fail to concisely describe this picture. Almost, but not quite: It's astounding.

The story, as anyone who's ever experienced the enchantment of the J.R.R. Tolkien fantasy novels upon which this one is based must know, is irresistibly gripping, and anything but simple.

In "The Return of the King," the Fellowship — entrusted with rescuing Middle Earth from extinction by the rampaging barbarian hordes of the Dark Lord Sauron — has been sundered. The wizard Gandalf and the Hobbit Pippin make their way to Gondor, the currently kingless kingdom whose brooding and unstable steward they must persuade to rouse his forces in resisting the encroaching tide of evil. Meanwhile, in a kingdom far away, the Elf Legolas, the Dwarf Gimli, the Hobbit Merry and the rightful-but-ambivalent king of Gondor, Aragorn, have joined forces with the fearless warriors of Rohan to do similar battle. And in Mordor, in the very heart of the dark land of Sauron, the Hobbits Sam and Frodo, guided by the mutant creature Gollum, are making their way through appalling dangers to cast Sauron's ring of evil power back into the fires of Mount Doom in which it was long ago forged.

This skeletal précis hardly begins to suggest the movie's abundant marvels and rich satisfactions. Jackson's cameras — whether zooming up the cliff-like ramparts of Minas Tirith, the encircled Gondorian capital, or soaring above vast, clamorous battlefields and through darkening skies filled with shrouded Nazgûl on their hideous, bat-winged serpents — never stop moving. Astonishing events are always in-progress, under way, pulling you into the action. The film's custom-crafted digital technologies — way out on the cutting edge of computer-generated imagery, or CGI — provide creatures and settings so persuasively "real" you sometimes want to leap from your seat to applaud the sheer exuberance of their execution. The Battle at Pelennor Fields, in particular — an extended scene teeming with hundreds of thousands of slavering Orcs, huge, lumbering trolls, and building-size saber-toothed battle elephants called Mûmakil — is amazing. Although surely influenced by the pioneering work that special-effects master Ray Harryhausen did some 40 years ago (in movies like "The 7th Voyage of Sinbad" and "Jason and the Argonauts"), it is simply unlike anything ever before seen on a movie screen.

Twenty-odd years ago, director George Lucas achieved some pretty rousing effects with his first three "Star Wars" movies. But Lucas' characters were wooden; emotional cartoons. (Harrison Ford reportedly once told Lucas that while it might be easy to write the films' dialogue, it was impossible to speak it.) The "Lord of the Rings" movies are very different.

The dialogue, for one thing, is beautifully written and sometimes poetic. And the actors are vividly talented. What hero has ever been more quietly magnetic than Viggo Mortensen's Aragorn, with his weary gaze, his disheveled charisma? Or more gravity-defyingly dashing than the Elf archer Legolas, played by Orlando Bloom? Could anyone better the regal bearing of Ian McKellen's Gandalf, or the curmudgeonly charm of John Rhys-Davies as the Dwarf Gimli? And who could improve upon the casting of the small-but-valiant Hobbits: Billy Boyd and Dominic Monaghan as the capering Pippin and Merry; Sean Astin (in an unusually moving performance) as the loyal Sam; and of course Elijah Wood as Frodo, the beleaguered Ring Bearer? Not to mention that CGI marvel, Gollum, whose incarnation once again transcends the usual limits of digital provenance to become a fully realized character, the Ring's most tragic victim.

Is "The Return of the King" the best of the "Rings" movies? I don't want to think of it that way myself. The three pictures were essentially filmed as one long epic, in one very long shoot, which has lent them an unusual dynamic continuity. Each one is part of a large and majestic achievement. But this one is the wrap-up, and a glorious one it turns out to be, a triumph on just about every filmmaking level. Believe me, you can't see it soon enough.

Kurt Loder