James Levine's cleaning lady's favorite opera is the one-act Salome. That's because her boss needs only one tuxedo to get through the performance. Normally, Levine changes sweat-soaked clothes, from underwear to bow tie, with every act of the more than 60 operas he conducts yearly at New York's Metropolitan Opera.

It is not yet known how many tuxedos Levine will drench on Oct. 22, when the Metropolitan celebrates its 100th birthday with an eight-hour spectacle boasting 70 of the world's biggest (literally, in some cases) opera stars lumbering across the stage and belting out a hit parade of arias. At the podium, waving his baton throughout, will be the now familiar, stocky, frizzy-haired, bespectacled figure of James Levine, at 40 the undisputed leader of America's—and perhaps the world's—foremost opera company.

Levine's rise at the Met has been allegro. He made his conducting debut there in 1971, was named principal conductor in 1973 and two years later became musical director. Last month Levine signed a five-year contract that, beginning in 1986, makes him the Met's artistic director. "I think we feel that this is finally Jimmy's house. The golden age of American opera has begun," says Ray Gniewek, Met concertmaster.

Being America's hottest young conductor and in charge of a $70 million company is no song and dance. "I work for the Met 24 hours a day" is Levine's favorite refrain. (Actually, he admits to at least four hours of sleep nightly.) His hectic schedule includes devising the Met's 200-plus performance calendar, deciding who will sing what and keeping temperamental stars happy, conducting rehearsals and performances, and acting as piano accompanist when favorite divas such as Renata Scotto and Kathleen Battle do recitals. And that's only during the Met's September-through-April home season. In the summer Levine is off to Chicago to conduct the Ravinia Festival and then jets to Europe for baton-waving stints at the celebrated Salzburg and Bayreuth festivals. Somewhere in there, he has managed to record more than 50 albums over the last dozen years.

All this music-making earns Levine an estimated $1 million a year but little time to spend it on nonmusical pursuits. Levine cheerfully confesses to not having seen a movie in years ("I refuse to stand in line"), not watching TV and not even glancing at newspapers. "I read reviews as they cross my desk," he says. "If there is anything relevant to me in the news, I find out from people I know."

He certainly doesn't find time to scan the fashion rags. When he is not donning and doffing tuxedos for performances, the 5'10" Levine's sartorial spectrum is limited to navy-blue sports shirts, matching polyester pants and scuffed brown desert boots. As for accessories, he fetchingly drapes a bath towel over his shoulder to mop up perspiration. "If I had to change my clothes to fit all my different activities in a day, there wouldn't be time for conducting," he explains. "So I developed this terrific uniform: comfortable, practical, and it looks nearly as good soaking wet as dry."

Levine's parents swear they brought him up to dress better at home in Cincinnati. His father, Larry, was in the garment trade as a manufacturer's salesman. His mother was a Broadway actress before marrying and settling down. His folks say they knew from the start that he was musically inclined by the rapt attention baby Jimmy paid to his father's warbled lullabies. "If we wanted to sleep late on a Sunday morning," recalls his father, "all we had to do was place a card table by his crib filled with his Victrola, records and a stack of graham crackers. He used to reach through the bars and amuse himself by the hour."

Just how musically inclined he was became apparent when, he started piano lessons at 4 and made his debut as a soloist with the Cincinnati Symphony at 10. His mother says Jimmy used to protest angrily when she made him stop practicing to go outside and play. Opera and conducting became part of Levine's musical life the first time he heard a touring Metropolitan Opera star sing with the Cincinnati Symphony at the Cincinnati Zoo. Thereafter, he would sit in on rehearsals, his grandmother's knitting needle in his hand, and conduct. He begged his father to buy him a miniature stage from the FAO Schwarz toy store and used it to guide tiny Carmens and Toscas to their inevitable tragic deaths.

In 1961 Levine enrolled in the prestigious Juilliard School of Music in New York City. Although only 18, Levine was placed in the school's postgraduate program and became its first student ever to double-major in conducting and piano. He dropped out of Juilliard in 1964, however, when George Szell, then maestro of the Cleveland Orchestra, made him an offer he couldn't refuse: the post of assistant conductor. Next stop: the Met.

Today, when not at the opera house, Levine makes his home in a luxury coop apartment on Manhattan's Central Park West (Diane Keaton and Dustin Hoffman are in the same building) and spends his infrequent days off at his 43-acre country retreat in Upstate New York.

Sharing these residences is Sue Thomson, Levine's housemate since 1971. Thomson, who has delicate good looks and dresses like a preppy L.L. Bean-catalog model, gave up playing oboe professionally to act as his constant companion. The relationship has done little to diminish Levine's reputation for having one of opera's most uninhibited sexual appetites—for any and everyone—since Don Giovanni. However, Levine dismisses such talk by saying, "I believe vehemently that a person's private life is more interesting than most people think, but much less so than people fantasize."

Need proof? Consider this: Collecting dinosaur bones is Levine's only serious hobby, but it is one he pursues with gusto. He frequently has the bones fashioned into jewelry. Sue sports a prehistoric belt buckle, and Levine's mother wails, "God, I've got jewelry made of dinosaur bones coming out of my ears." All gifts from a son whose mammoth talents are making opera anything but extinct.