Hallelujah! It's celestial take-off time of a musical fantasy, Sidney Lumet's spectacular, joyous production of "The Wiz" generates a mood of wonder and sentimental rapture recalling the arrival of the Mother Ship in "Close Encounters of the Third Kind."

Indeed, Lumet and his inspired collaborators have succeeded in fabricating and navigating one majectic, rabble-rousing Mother Ship of a musical, a sublimely happy moviegoing experience.

At its emotional peaks - the "Be a Lion" number, in which Diana Ross' Dorothy restores the morale of Ted Ross' magnificiently costumed Cowardly Lion, or the elaborate, energetic dance ensembles, or Lena Horne's appearance as the good witch Glinda the movie achieves a lyric intensity that thrills you down to your toesies.

During the jubilant "Gonna Be a Brand-New Day" the sight of Louis Johnson's dancers and the sound of Quincy Jones' arrangements had me fancying that the theater auditorium might lift off its foundation and sail away. When the lyric spirit starts moving expect dancing in the aisles, dancing in the lobby and dancing in the streets.

"The Wiz," which opens today at the Embassy Circle and K-B Bethesda in Dolbo Stereo and at the Capri, Centre and Landover Mall in monaural prints, is reputed to be the most expensive film musical ever made. Cost estimates have ranged from $14 million to $35 million.

At the moment the film's commercial potential is being underrated, and perhaps "The Wiz" will need to overcome special kinds of prejudice and sales resistance before attracting the mass audience it deserves.

The resistance could take several forms: reluctance to attend a movie with an all-black cast, even one including Ross, Horne, Richard Pryor, Michael Jackson and Nipsey Russell; a misconception that the film merely duplicates the stage show: pejudice against reinterpreting the classic "The Wizard of Oz,"; and outrage that Dorothy should age to accommodate the starring presence of Diana Ross.

I felt the last two forms of resistance myself, but in the end they seemed negligible for a simple reason: You come out of this movie feeling blissfully moved and glad to be alive.

The cost of "The Wiz" is beside the point, since the filmmakers have more than justified the expense. Audiences can exult in the inventive prodigality of Tony Walton's sets and costumes or in the humorous luxury of the Emerald City fashion show, where fickle Slaves of Fashion promenade in a series of green, red and gold evening togs designed by Scott Barrie, Bill Blass, Stephen Burrows, Oscar de la Renta, Halston and many others.

Does it matter how much was spent on illusions as beguiling as the playful Manhattan skyline dominated by five Chrysler Buildings or the yellow sun that rises over the Battery to mature into a literal Big Apple?

The dream vision of New York City created in "The Wiz" is a surreal delight, reminiscent of the compressed, rearranged urban vistas conjured up in Saul Steinberg's drawings.

"The Wiz" follows the plot of "The Wizard of Oz" fairly closely while transposing the dream world Dorothy finds herself lost in from a rural, to a contemporary urban landscape. The regional dialect becomes a tangy black vernacular.

The new heroine is identified as a young kindergarten teacher who lives with her aunt and uncle in a middle-class Harlem apartment house. The movie begins with a family holiday gathering presided over by the aunt, named Em and portrayed by Theresa Merritt, whose singing voice has an emotional warmth and intimacy that sets a lovely vocal pattern for the entire show.

Dorothy is depicted as odd girl out - by her own choice - in an affectionate family circle. She appears to suffer from a mysterious but acute case of shyness. In a little ditty especially composed for the film by Quincy Jones, Nick Ashford & Valerie Simpson. Dorothy makes a feeble case for her timidity: "Don't know what I'm made of/What am I afraid of?/Can I go on not knowing?"

Before she can begin to resolve this anxiety, her little dog Toto dashes out of the apartment. Pursuing him outside, Dorothy becomes blinded and lost in a snowstorm that sweeps her up and deposits her in Oz, an alternately sinister and entrancing abstraction of New York.

Dorothy the teacher encounters some familiar figures among the wittily scrambled New York landmarks - Michael Jackson as a sweet-tempered kid scarecrow; Nipsey Russell as a beat-up amusement park tinman of unexpected dignity and show biz savvy; Ted Ross as a cowardly lion concealed inside one of the statues at the New York Public Library; Richard Pryor as a fraudulent wizard; Mabel King as a wicked witch and Lena horne as a benevolent witch. - But these characters lack prototypes in her waking life. The spring out of "The Wizard of Oz" rather than the new Dorothy's own circle of acquaintances.

Given this apparent trick of Dorothy's imagination: screenwriter Joel Schucmacher should have devised a prologue in which Dorothy was also shown working as a teacher. The movie needs a little documentation of Dorothy's professional setting to justify changing the heroine from an adolescent to an adult.

One does detect occasional echoes from the classroom. Michael Jackson's scarecrow is obviously conceived as a symbol of salvageable youth. His head is stuffed full of thoughts he despairs of organizing or understanding; they inspire the low-minded crows who torment him to merciless ridicule. Friday Dorothy shows her first bit of spunk when she shoos these mug no-accounts away and tries to encourage the scarecrow's intellectual aspirations.

Like "The Wizard of Oz" before it, "The Wiz" appreciates the enduring inspirational appeal of the original L. Frank Baum fantasy. Has anyone ever dreamed up a sounder propagandistic fable? Dorothy is trying to find her way home, while the scarecrow longs for brains, the tinman for a heart and the lion for courage. Everyone feels the need of scrutiny, intelligence, compassion and valor and laments their absence or loss. Everyone appreciates a child's special need for those things. The social content of "The Wiz" gives this need a special urgency and poignandy.

There would be less strain on Diana Ross' performance if the anxiety expressed by her Dorothy stemmed from a tender-hearted preoccupation with her pupils, whose behavior might be reflected in the behavior of her imaginary companions on the road to Oz. Explained as mere shyness, Ross' neurotic skittishness in the early scenes may appear insufferably affected. It's difficult to accept her as the family wallflower. One needs a hint or two of the delicate rapport she establishes with her companions and of the happiness waiting for incandescent release in her singing and dancing.

The ensemble nature of the show and the presence of strong supporting performers prevent Ross from induling the vain excesses of her recent television special, where she appeared to wallow in adoration. The literally heavenly appearance of Lena Horne in "The Wiz" may be enjoyed in part as a rebuke to that TV "tribute."

Horne repeats a song, "Belive in Yourself," that Ross has just finished singing to her companions. Horne's fervor makes Ross' rendition seem a trifle blah by comparison, but Ross picks up on the fervor in her soaring finale, "Home," shot in the straight-forward, heart-stopping look-the-audience-dead-in-the-eye style of Barbara Streisand's "My Man" solo at the close of "Funny Girl."

Ted Ross and Mable King are the indispensable holdovers from the original Broadway production. Ross looks as beautiful as Jean Marais' Beast in Walton's lion costume, and he has a commanding pair of eyes and set of lungs. He will be long remembered for two inspired moments; the way he looks at Dorothy while licking her hand during the opening stanzas of "Be a Lion" and his brief improvisation of "How High the Moon" after being exposed to big-city poppy dust.

A delightfully swaggering, grotesque, implacable villainess, King takes immediate command of her single number, "Don't Nobody Bring Me No Bad News," starting a rousing, show-stopping momentum that carries right through the production number celebrating her destruction, "Brand-New Day."

The arrangements and singing voices seem to envelop the lyrics in warmth and color compensating for the evanescent qualify of the words themselves. Ross and Nipsey Russell, who does himself proud in a belated movie debut, are especially effective at soft, intimate phrasing.

The movie is sprinkled with pretty illustrative details, like the rising of the Big Apple or the inserts of the black cherubs who surround Glinda in her starry sphere or the moment when King's liberated slavies slither out of their downtrodden skins to become a sinewy dance troupe.

Sidney Lumet may never have directed afilm musical before, but he apparently knew what he wanted from this opportunity and surrounded himself with collaborators who knew how to create an environment of unique, lyric cinematic enhantment. Tony Walton's scenic inventions surpass his contributions to "Mary Poppins." Cinematographer Oswasd Morris, who also photographed "Oliver!" and "Fiddler on the Roof," always seems to be in the right expressive position, whether the scene is intimate or panoramic. Dede Allen's editing accentuates the pictorial elegance by maintaining continuity of movement and musical integrity. The shifts in angle invariably harmonize with the scoring, and the patterns traced by Louis Johnson's dancers are within the picture frame.

Lument has described the film as his "valentine to New York." No director has ever orchestrated a more stirring and captivating tribute to the tarnished but magnetic old Big Town.

"The Wiz" is a marvel, and it should be an enduring source of pleasure to several generations of moviegoing kids, families and fantasists.