LOS ANGELES -- If we had a time machine and wanted to relive the moment when the artistic world first went "modern," probably the ideal target would be Paris on the evening of May 29, 1913. That was the night the ballet "Le Sacre du Printemps" ("The Rite of Spring") burst upon the public like an esthetic Hiroshima, causing a riot and setting off the biggest shock waves in the history of the performing arts.

The time machine is at hand. The Joffrey Ballet restages the 1913 version of "Sacre" here at the Los Angeles Music Center tonight with Vaslav Nijinsky's restored choreography and Nicholas Roerich's original designs complementing Stravinsky's revolutionary score. No one expects that police will have to be called in to quell the disturbance, as in the old days, but we may well learn a thing or two about where the discord, violence and iconoclasm of our contemporary arts came from, and why we continue to be gripped and fascinated by them.

We also may begin to fill in a notorious gap in artistic history. Until very recent times no one imagined there was any practical possibility of reviving the original production of "Sacre." The choreography and designs were thought to be lost.

Stravinsky's music, of course, survived both its public birth and storms of criticism, eventually becoming what Lincoln Kirstein called "our era's criterion of innovative genius." Nowadays we smile at a Boston reviewer's satiric jingle: "Who wrote this fiendish 'Rite of Spring'? What right had he to write the thing? Against our helpless ears to fling its clish-clash cling-clang bing-bang-bing?"

What's been overlooked except by a handful of die-hard dance fanatics is that Nijinsky's equally revolutionary choreography -- at the time, some thought it more radical in concept than Stravinsky's ferocious score -- and Roerich's landmark primitivist designs (Stravinsky dedicated the score to him) haven't been seen in 74 years. Diaghilev's Ballets Russes, which commissioned "Sacre," performed the Nijinsky version only eight times, after which the production disappeared, to all intents and purposes. Roerich's career flourished, but Nijinsky, by then a legendary dancer, split with Diaghilev, went insane and spent his final years in asylums.

Stravinsky's music not only took on an independent life in the concert hall, but also continued to be exploited choreographically all over the map -- by Le'onide Massine, Lester Horton, Maurice Be'jart, Kenneth MacMillan, Mary Wigman, Pina Bausch, Martha Graham and Paul Taylor, among others. At least 25 dance versions have been presented since the scandalous Nijinsky premiere.

Nijinsky's choreography, though, seemed irretrievable. Yet it was probably the single most staggering rebellion against balletic tradition since Isadora Duncan, and far more akin to contemporary choreographic thought.

Nijinsky, working totally against the grain of his own traditional training and brilliant classical virtuosity, created a new choreographic mode based on angular shape, pounding, syncopated rhythms and stark, percussive movement. In striving to realize the Stravinsky-Roerich scenario of an ancient pagan sacrificial ceremony -- in which a young woman, the Chosen One, dances herself to death to induce the renewal of spring -- Nijinsky at a single bound invented the first truly modern dance. Through the accidents of fate, no logical sequel was forthcoming in the ballet world, save for the ballets of Nijinsky's sister Bronislava, whose choreographic achievements, like those of her brother, were long underestimated and neglected.

Robert Joffrey began thinking about the possibility of restoring Nijinsky's "Sacre" as far back as 1955, when he lived in England for some months with Marie Rambert, a Dalcroze disciple -- and later one of the seminal figures of British ballet -- who had worked closely with Nijinsky in staging the 1913 "Sacre."

At a press conference yesterday at the Music Center, the fruits of Joffrey's dream were clearly ripe for picking. The American dancer-scholar Millicent Hodson and her British art historian husband Kenneth Archer spoke about and demonstrated the results of a decade's research on three continents -- work that laid the foundation for the Joffrey Ballet's new production. Ballerina Beatriz Rodriguez, who'll dance the Chosen One tonight, performed some stirring excerpts with the help of pianist Stanley Babin and a brief orchestral tape.

Joffrey met Hodson in 1971 when she was a graduate student at the University of California at Berkeley, and the two of them discovered they shared the pipe dream of a restored "Sacre." In England, at about the same time, Archer was becoming interested in Roerich and his archeological paintings. It was "Sacre" that brought Hodson and Archer together a decade later in a storybook courtship ignited by the elusive Nijinsky-Stravinsky-Roerich masterpiece.

By 1979, Hodson had begun to work seriously on the "Sacre" restoration, with Joffrey's encouragement. In 1981, she went to England on a research grant to work with Lambert, whose piano score of "Sacre," with handwritten notes and directions by both Lambert and Stravinsky, became a major resource for the project. By then, too, she had happened on a Roerich museum in New York City, the director of which told her, "Oh, you must consult Kenneth Archer in London; he knows lots about 'Sacre.' " When she took the advice, research led to romance, and the couple has been working side by side ever since toward the goal of tonight's premiere. They've also completed a book about their research, to be published in Great Britain shortly.

Hodson and Archer had to piece their staging together on the basis of mostly secondhand documentary evidence. Though some of Roerich's designs and costumes did turn up in museums, archives and art auctions, Nijinsky's choreography had to be retrieved with the help of still photographs, drawings, verbal descriptions, eyewitness accounts and the like.

Hodson says she sometimes had to "make bridges" between passages that were firmly known or safely guessed and those that were wholly missing. She says Joffrey, who supervised the entire reconstruction process, is convinced that 85 percent of her staging represents absolutely authentic Nijinsky choreography.

"Sacre" will be given four performances in Los Angeles, and the Joffrey troupe will take it next to New York in late October for another five performances at City Center. The Nationwide Dance Critics Association will hold a three-day symposium on "Sacre" Nov. 5-7 in conjunction with the Joffrey appearances.