"When the curtain went up, it was like being in church," one spectator remembers of a Ballets Russes production in 1910. "People were awestruck by the spectacle."

It was a new kind of ballet designed, composed, choreographed and danced by Russia's finest artists. And the entrepreneurial genius behind the group -- which profoundly influenced art and fashion in its time and after -- was Sergei Pavlovich Diaghilev.

"From Diaghilev," says George Balanchine, director of the New Yokr City Ballet, "I learned to be an artist."

Diaghilev, whose exotic productions for the Ballets Russes in Paris over two decades jolted the fin de siecle from its restrained elegance and bland colors, is the subject of an extraordinary exhibition at New York's Metropolitan Museum on the 50th anniversary of his death called "Diaghilev: Costumes and Designs of the Ballets Russes."

The show combines costumes and graphic arts from major productions of the Ballets Russes to recreate the world of Diaghilev and the artists he enlisted to work with him.

"He brought with him a tone of savagery, Oriental refinement, extraordinary design and color, as well as moods, music and dancing that had never before been seen or heard in Western Europe," writes Diana Vreeland, fashion doyenne and special consultant to the Costume Institute, in the preface to the show's catalogue. "The influence of Diaghilev, that magician of the theater, changed the culture of our century, and the page was turned forever on La Belle Epogue."

"You have to imagine the ladies in the audience -- wearing heavy corsets, pale-colored dresses with layers of ruffles, and huge dog collars -- watching the women on stage wearing these body-revealing styles and moving so freely," says Stella Blum, curator of the Costume Institute, who believes that the Rusian Ballet was the catalyst that made modern dress happen. Paul Poiret had been moving in the direction of corsetless styles and more exotic designs, but "with the Ballets Russes there was crystallization of this new direction."

Diaghilev enlisted the top talents of his era, getting diverse artists to work together and getting some very swelled heads to accept shared honors. During a reign of 20 years he peopled his world with the talents of Stravinsky. Ravel, Debussy, Bakst, Fokine, Benois, Matisse, Picasso, Cocteau, Proust and Claudel, plus dancers Pavlova (though only for one year), Nijinsky and Ida Rubinstein.

Diaghiley was born in Perm, Russia in 1872 into a family with a military tradition. At age 18 he went to St. Petersburg University to study law but enrolled, as well, in the music conservatory. It was there that he became part of an artistic circle including Bakst and Benois -- cultural revolutionaries at the time, although totally apolitical. Through them he became a connoisseur of painting and an art critic.

In 1899 he founded an art magazine and by 1908 he had became in impresario, presented Boris Gudounov in Paris with famed basso Feodor Chaliapin, and decided to import Russian ballet to Paris. He tapped the best dancers of the Imperial Theatre and his friends from the art circle including Bakst and Benois. The Ballets Russes opened May 19, 1909 at the Theatre du Chatelet.

"His productions hit Parisians in the gut once and forever." says Vreeland, whose previous exhibitions have generated a new from of costume presentation and influenced the fashion industry.

Vreeland was a young girl in Diahilev's Paris. He was a friend of her mother and she remembers him coming to her house. "He was extraordinary looking and stood with great style," she says. Vreeland later studied in New York with Fokine, the celebrated Russian Imperial ballet master.)

Despite the extraordinary influence and success of the Diaghilev producations, they were not a rich company. Many of the costumes were made quickly and in poor fabric; others were reworked for several performances and arrived for the exhibition in shabby condition. The only ones in good repair are from unsuccessful productions, like the Bakst bejewelled garments for "Le Dieu blue" (1912).

It took four days for Elizabeth Lawrence and her team of restorers (most volunteers) to repair a costume from "Scheherazade" (1910) which arrived at the Met in shreds. All embroidery and appliques from the original garment were removed, and it was covered with layers of nylon and silk closely matching the original fabric. Then the decoration was returned in its original from. Such restoration, Blum says, gives the viewer a chance to see what the costume looked like on stage without destroying the integrity of the design.

If the current exhibit -- which continues until June -- is smaller in scope than Vreeland's earlier shows at the Met (the glamour of Hollywood; the glories of Russian costume -- a popular favorite; the designes of the 1910s, '20s and '30s, and others) it is undoubtedly because the museum has also mounted the Tut exhibition, the Temple of Dendur and the Dresden show.

Buut the scope does not diminish the show's impact, and it brings to life an extraordinary and influential period.

Blum isn't sure that the display will have an identifiable influence on current fashion. "Haven't we had our fill of ethnic costumes?" Blum asks, pointing to Russian folk motifs in many of the costumes. "From these the designers may take only the idea of a pattern of applique."

"But look at these Bakst costumes," she says, pointing to several tunics over shorts, in strong colors in big prints that were made for "Daphnis et Chole." "Can't you just see a man or woman wearing that to the beach, next summer?"

And about the diaphanous dresses from "Narcisse" also by Bakst: "Those might make great disco dresses. Couldn't you see them at Studio 54?"