The ingenious Muppet organization has upstaged the critis by advancing their utterly delightful new movie, "The Great Muppet Caper," with a droll souvenir book in which raves are anticipated by author Ellis Weiner. "The only movie in history to justify movies, history -- even life itself," cheers the Weiner exaggeration of Pauline Kael, while his Stanley Kauffmann declares "It is -- no lesser term will do -- the stuff of great art," and his Andrew Sarris threatens to retire out of sheer speechlessness.

While it may not make movie criticism superfluous, "The Great Muppet Caper" is certain to disarm many an admiring reviewer and also to charm legions of nonprofessional moviegoers. The first feature directed by Muppet creator Jim Henson, "Caper" reveals a stylistic confidence that was missing in "The Muppet Movie."

"Caper," makes affectionate, rejuvenating sport of romantic comedy and musical comedy conventions. For example, Henson has the Muppet called Animal do a ravenous impression of MGM's Leo the Lion.

The playful mood is sustained through the opening credits, which introduce Kermit the Frog, Fozzie Bear and Gonzo descending in a balloon and commenting on the printed matter as it appears beneath them. "What does B.S.C. stand for?" Fozzie asks as the credit for cinematographer Oswald Morris appears. The remarkable thing is that this small talk isn't mere inside-joking: The repartee seems appropriate to the Muppets as characters. For example, it seems very much like Fozzie to ask if anyone really reads all those names and very much like Kermit to reply, "Sure, these people all have families, too."

Landing in the middle of a busy city street, the three balloonists leap into a rousing curtain-raiser of a production number, "Hey, a Movie!" The first of five new Joe Raposo songs, it sets the caper plot in motion and establishes Henson's pictorial command while also proving a gratuitous treat. Tastier treats remain to be relished when Miss Piggy enters. She inspires Henson and his collaborators to satiric musical comedy glory, first in an elegant nightclub dance ensemble recalling the Big White Sets built at RKO for Astaire and Rogers and then in a dream water ballet spoofing Busby Berkeley's maddest brainstorms for Esther Williams.

Kermit and Fozzie, who fancy themselves identical twins and aspire to be investigative reporters, blow their chance with editor Jack Warden by missing a big story that happens literally behind their backs -- the daring daylight theft of an expensive bauble from Lady Holiday (Diana Rigg), London's most fashionable dress designer. At the crucial moment Kermit, Fozzie and Gonzo, their photographer, are preoccupied with interviewing a chicken. Pounding his desk in frustration, which causes objects to jump into the air with hilarious emphasis, Warden dismisses the inattentive cubs. Hoping to make amends and perhaps solve the robbery, too, the Muppets follow Lady Holiday to London, riding ultra-economy in the luggage compartment of a jet. "It must be 50 below in here," Kermit remarks with endearing resignation.

One of the charms of the dialogue is this special awareness of sensations and feelings as experienced by a Muppet. There's a sweet adaptability about their reactions, also reflected in Gonzo's "Hey, this is nice!" upon entering the flea-bitten Happiness Hotel, a Muppet flophouse. There's something even more captivating about his exclamation upon getting his beak caught in an elevator door: "Get your nose in here! It's really fun!" It seems an inspired touch to suggest that these vulnerable little creatures are also peculiarly nerveless and invulnerable in certain respects. Obvious when you think of it, but you'd need Henson's identification with his creations to think of it in the first place.

Although craving a modeling career, Miss Piggy settles for a job as Lady Holiday's receptionist. When Kermit arrives, she swoons and neglects to correct his misapprehension that she must be Lady Holiday. There's not a great deal of mystery about the robbery gang victimizing the designer. Suspicion falls immediately on her ne'er-do-well playboy brother Nicky, played by Charles Grodin. What one doesn't anticipate is Nicky's hopeless infatuation with Miss Piggy and the exquisite deadpan humor Grodin brings to his passion. Watching him attempt to alienate the affections of Miss Piggy, who remains steadfast in her devotion to Kermit, is a savory comic experience.

Henson's control is so good that he effortlessly picks up the plot thread after indulging in all kinds of entertaining digressions -- production numbers, throwaway gags about moviemaking, even elaborate shaggy-dog routines. For example, what appears to be a fleeting bit by John Cleese and Joan Sanderson as a phlegmatic English couple is spun out into a lengthy skit, but the more detailed their inertia becomes, the funnier it becomes. Peter Falk turns up in an uncredited bit as a bystander who accosts Kermit with a self-centered tale of woe, after claiming that he could tell precisely what was eating the melancholy frog. Ultimately, Kermit is forced to brush off the presumptuous intruder: "I hate to be rude, but we're trying to do a movie here."

Henson and his associates have, in fact, done themselves proud. They've made such a spiffy movie that it wouldn't be a bad idea if certain people struggling with comedy stylization (you listening, Hal Needham and Mel Brooks?) went to school with "The Great Muppet Caper."

It seems inevitable that the film may be avoided by some adolescents and adults misled by the "G" rating. You can't stop some people from cutting off their noses to spite their faces, but the fact remains that "Caper" is not only a funny, wholesome attraction but also an enviably witty and sophisticated attraction. Don't hesitate to stick their noses into theaters playing "Caper." As Gonzo says, "It's really fun!"