New Yorkers jamming the 25th annual Central Park Shakespeare Festival perhaps found the previewing show a midsummer night's scream. The Pirates of Penzance sure ain't the Bard, nor are the big draws the accustomed stage-trained heavies like Meryl Streep or James Earl Jones. They are Linda Ronstadt and teen throb Rex Smith.

But once impresario Joe Papp opted to mount the Gilbert and Sullivan operetta to stir the jaded natives, the casting of country-rocker Ronstadt seemed interesting. But why pair her with Smith, 24, best known for treacly hit 45s competing with Andy and Leif and Shaun? Explains Papp: "Linda said, 'Get me somebody cute.' Rex is cute." Linda may be sorry. The official premiere and reviews aren't due until this week, but so far Rex seems to be more than holding the stage with Ronstadt (not to mention with eminent troupers Patricia Routledge and George Rose).

During the Pirates rehearsals, Rex indicated that he'd like to be more than the sum of his pecs by submitting to his first professional voice coach and learning to waltz. As for the limelight, that he can handle and has the stats to prove it. "Four years, four albums, three tours, 20,000 seats a night," Rex recites boastfully. "In 19761 was just doing hard rock'n'roll and riding my motorcycle. Suddenly I was hot as a pistol—I woke up one day a teen idol."

The breakthrough was his 1979 smash You Take My Breath Away, and the question is whether it subsequently took away his three-year marriage to Lois Smith, now 25 and a Bunny at Manhattan's Playboy hutch. Mutters Rex's manager, Steve Leber: "There are all those little girls out there in love with him!" So to Leber (who claims to have a $350,000 investment in Rex's career), a wife is murder imagewise, and Rex is now publicly backing away from a marriage that he confides "started like Swept A way and ended like Lion in Winter. It's under litigation," he says. "I pay the bills. We're separated, we have separate apartments, we have our own space." But when wife Lois is asked if separation or divorce papers have been drawn, she responds with a flat "No," insisting that they still share the same Upper East Side pad. "The whole thing is sticky," Lois concedes. "His publicity always says his marital status is 'single.' I'm not bothered by it—life with an entertainer isn't easy."

Indeed, Rex's own life was once easier while growing up in Atlanta, the son of an advertising executive with Prudential. He once toyed with "going into dentistry and playing golf three days a week," but conventional ambition soon lost its appeal. Seems that during a siege of chicken pox he let his hair grow long and when he finally returned to junior varsity football practice, "two guys trampled my ass. 'Screw this,' " he says he told himself, " 'I can meet girls without breaking my leg.' " After graduating from high school, he followed his three older brothers into music (Mike, 28, sang with the rock band Starz; Webster, 26, is a graduate of the Manhattan School of Music; and Evan, 30, is a rock lighting designer).

By 1978 Rex had graduated from bar gigs to opening for Ted Nugent. He was cast in the TV flick Sooner or Later, which introduced You Take My Breath Away. Before it aired, Rex took over the Broadway lead in Grease, and soon got a role in Joe Brooks' still-unreleased movie, Headin' for Broadway. Earlier this year he moved to L.A. "because I felt burned out by New York."

The Coast did have its fleshy appeal. "The first month my apartment had a revolving door," Rex smirks. But he recalls Beverly Hills neighbor Joan Hackett being "mad at me—my dog [Pal, a pit bull] scratched her Mercedes." Also, he complains that, unlike in New York, "I couldn't go out and find a restaurant open at 10 o'clock within two miles." So the role in Pirates sounded appealing.

That meant at least proximity with wife Lois. "At first," she reports, "he had a superinflated ego. It's money that does it, being able to go out and do things like buy six shirts. But he comes back." Rex admits that lately "we're being friendly." And long-range? "If we work back together, that's fine," allows Rex. "I want a family and all that junk."

As for his career, he's decided, "Movies are the class act." But clearly he is sweating out the Pirates reviews no less than Ronstadt. "This is the most elite group of actors there is," reckons Rex of his fellow Savoyards, "and you can't buy this kind of education."