One look at Brigitte Bardot's ripening sensuality in 1957's And God Created Woman convinced generations of male admirers that it was so. But, now more than ever, what Bardot's female fans want to know is: Who did her hair? Indeed, not since Bardot apotheosized the messy blond bun more than 30 years ago have tousled tresses caused such titillation.

First to re-create the mane event was 20-year-old German megamodel Claudia Schiffer in a series of enticing Guess? jeans ads. "The idea," says Donald of Bruno Dessange in Paris, who coiffed Claudia, "was to create psychological desire." And ooh-la-la, did he. With her unkempt bun, fake lashes and full-lipped pout, the voluptuous blond became an instant tress-setter.

The "new" Ivana Trump was quick to pick up on the Bardot revival. Unceremoniously dumped last February by you-know-who, Ivana traded in The Don for The Do and turned up triumphant—hair stacked atop her head—on Vogue's May cover. The allure of the pileup, explains Maury Hopson, the New York City hairstylist who created it, comes from its disheveled look, "like she just got out of bed.

"There was a period when women were proving themselves in 'a man's world,' " he says, "dressing like men, looking terribly groomed." No more, he says. "The Bardot look is very sexy. It says 'it's okay to play around.' " All of which sounds dandy for the boudoir, but will it work in the boardroom? Not likely, says Ellen Von Unwerth, who photographed Schiffer for the Guess? ads: "I don't think real women will be tempted to copy the look."

Guess again. "Women are coming in with Claudia's pictures and asking for that look every day," says Charles Booth, of New York's posh La Coupe salon. And why not? "It's easy to care for," he says, "and creates an illusion of both height and a long neck." But, warns equally Bardot-bom-barded Paris hairdresser Jean-Marc Maniatis, "the Bardot look of the '90s is not just straggly fair hair tied in a bun." Right, says Hopson, who reworks Ivana's French twist twice a week. "If women want to do it at home, they'll need a lesson first." Otherwise, he insists, they'll get a do that just won't sizzle.