PARIS — “Monsieur Klein,” purrs the host of the Plaza Athenee’s posh, fashion-filled restaurant. “I’d like to present to you my livre d’or one day, where I have designs of the grandest couturiers. You must take part.”

“After the defile, s’il vous plait,” replies Michel Klein, lowering his eyes with a bashful smile.

For the house of Guy Laroche’s baby couturier, who makes his widely anticipated and highly publicized debut on Jan. 18, life on the swank Avenue Montaigne wasn’t always this sweet.

In fact, it was only four years ago that Klein was refused lunching privileges at this same restaurant for not wearing the required jacket and tie. Now, after moving up to the highest ranks of fashion’s grand army, he is treated like a prince — even sans cravate.

Klein himself, at 36, is rather impressed by the weight his new status carries. Recently he came to the restaurant with designer John Galliano.

“Did he have a skirt on?” Klein says. “I don’t know, but he had something strange on, and a silk blouse unbuttoned to here, and a pink mutton jacket.” “Your guest is not dressed properly for the situation,” the manager said, but when Klein turned to go, the manager demurred and led an eager Galliano off to fetch one of the hotels “leftover” jackets. Galliano came back jacket-clad.

“Only he took off his shirt and was bare-breasted, fur hat and all,” Klein says, laughing. “Then we sat down.”

Even with his new influence, though, Klein’s not pushing his power to shock as his good friend Galliano does. He has but one simple goal in his challenging new post: to deliver clothes that “correspond to daily life.” “The idea is to refine the things we wear every day. There’s an imbalance between the couture and what women want now,” explains the designer, who was asked to take over the house’s couture after Guy Laroche’s hand-picked successor, Angelo Tarlazzi, bowed out last season.

Now one of the youngest Paris couturiers, Michel is not only out to change the face of Laroche, but also to rejuvenate couture.

“How can everybody be saying couture is dead when they are so excited about it?” Klein says. “I’ve never had so many previews and interviews in my life. The couture obviously means something.

“What I’ve done, in my view, is so different from what has been done in couture lately,” he goes on. “People should have a crush on clothes again. They have a crush on the Chanel bag today and that’s not fair, because it should really be something that makes you look seducing, sexy or makes you think, ‘I would love to divorce in that dress.’ You know, like those George Cukor films where it seems like the dress was made for the situation? I like the idea of something that’s meant for life.” That means no splashy stunts or theatrical grandeur on Laroche’s runway this season. Klein is taking the pared-down path — as he does in his signature rtw collection.

“Simple things with a very luxurious finish,” he says.

It’s a risk, admits the designer, who is eschewing many of the old-fashioned couture traditions. Take accessories, for example.

“The rule in couture is to have lots of jewels and to make women look rich. But I don’t want to feel these pressures,” he says. “It’s a pity when you look at the clothes after a Chanel show. There are some very beautiful dresses, but it’s like being insecure. Though I’m not sure Karl Lagerfeld is ever insecure, it looks like — I don’t know — that he doesn’t think the dress is right, that he adds so much that it’s hidden. Which I don’t think is normal, because he knows how to do a dress.

“Sometimes 20 necklaces, four belts and moon boots are not going to make the dress look prettier,” Klein concludes. “It may make the press talk a little bit more, but that’s not what I want to make the press talk about.”

Klein is after a different kind of buzz.

“I’d like to succeed in making a cut that is going to last and make clothes worth buying,” he says.

But there’s one looming question: Is there a demand for simple cuts in couture that one might just as easily find in pret-a-porter? “I’m sure when you wear couture — and I never wore a couture suit — but I’m sure when you wear it, it’s worth it. There is a big difference,” Klein says with a smile. “Of course it’s crazy,” he adds. “There’s a wood-beaded kimono that’s worth about 100,000 francs, or maybe more, in the collection. It’s crazy, but why not? If it’s really something special, it’s okay.”

In the midst of trying to change Laroche’s image, there’s also a practical side to Klein’s couture.

“It’s not like we want to lower the prices and quality, we just want to make the price what it should be,” he explains.

And, in fact, the classic pantsuit this season will be priced at $7,900 to $8,700 (45,000 to 50,000 francs at current exchange rates). Last season, according to the designer, the suit cost 75,000 to 80,000 francs.

It’s the American ladies Klein is after.

“They are the ones buying couture and they really think about the way they look,” he says. “Those rich American women have some of the best figures, don’t you think — when you see those front rows?”

He was given carte blanche to create the 61-piece collection. “I had absolutely no rules. They said, ‘You have to build a new image for Guy Laroche,’ period,” Klein says. The collection will be full of easy long silk jersey dresses, mariner tops, lots of black and navy, subtle embroideries and classic pantsuits with an Asian edge. The “Laroche image” is badly in need of a facelift, claims Klein.

“When you think of Saint Laurent, you think of the tuxedo, the satin dresses; you think of pink and red. When you think of Chanel, you think of the suit. When you think of Christian [Lacroix], you think of embroideries. When you think of Laroche,” Klein says, “you don’t think of anything.

“Except ladies — lady clothes. I felt that the perfume was stronger than the clothes.”

And so, with the help of his reinterpreted signature Mao suit — “a standard pantsuit that will be reinvented every season” — Michel hopes to slowly repaint the faded Laroche picture. After all, if the Chinese jacket has worked in the designer’s own rtw collection for eight years, why not upgrade it for the couture?

“It was the only uniform that didn’t look like a uniform, and with jeans, I realized, it was the only thing I have been wearing since I was at school,” the designer says. “I’ve done it in 50 different fabrics for rtw already.” And next week he’ll show a couture version in a luxurious black beaded chiffon.

But “the most important suit,” he explains, “is an interpretation of this idea, but it’s with a real jacket, shoulder pads and in silk crepe.” Klein’s Oriental obsession, which will also turn up in mandarin mules, kimonos and harem pants, springs from no particular point, he says. Neither, for that matter, does his interest in fashion.

“It was more the way of life that I wanted,” says the lanky designer, who grew up in Paris’s stylish, intellectual Saint Germain district. His parents, both psychoanalysts, ran with a fashion crowd, including the Jacobsons of Dorothee Bis, photographer William Klein and designer Christiane Bailly — who, Michel says, influenced him as early on as age 13. “There was Azzedine always there [at Bailly’s house], sewing for a client. I saw how they were living: eating spaghetti, 14 at a table every night, not having that much money, but being free and happy,” says Klein. The couturier has been working 12 hours a day — “I never imagined I could work this hard and actually like it” — prepping for the two shows he will present next week at the Hotel Ritz. He’s using whatever top models will still be in town, including Tatiana and Naomi, with Linda Cantello for makeup and Yannick d’IS for hair. Also pitching in are Christian Louboutin, who is doing the embroidered shoes; Stephen Jones, who is doing the hats, and Tom Dixon, who is doing the jewelry.

“You know, I’ve never passed exams because I hate them. Not even my driving exam,” says the semi-stressed Klein.

“But here I have chosen a business where I have an exam every six months. It’s totally masochistic!” he laughs, knowing that next week is his biggest test yet. “Some people will think it’s too much Michel Klein, some people will think it’s too simple. But,” he adds, “you can’t please everyone.”