The studio at 5 avenue Marceau, 1966

The studio at 5 avenue Marceau, 1966. Betty Catroux stands in front of a mirror wearing a man's tuxedo jacket, trousers cut slim enough to break at the ankle, a white shirt open two buttons. Yves Saint Laurent circles her once, pins the shoulder, steps back. He does not sketch what he sees. He already knows.

Catroux did not walk runways. She did not appear in campaigns. What she did was wear Saint Laurent's clothes as though she had designed them herself—with the insouciance of someone who understood that a dinner jacket was not costume, but Tuesday. She was tall, dark-haired, androgynous in the way that made other women reconsider their entire wardrobe. Saint Laurent saw in her what he wanted every woman to feel: that borrowed menswear, properly cut, was more seductive than anything explicitly designed to seduce.

She became the blueprint for Le Smoking, introduced in 1966, the year they met. The tuxedo was not new—Marlene Dietrich had worn trousers in the thirties, Katharine Hepburn owned a closet of them—but Saint Laurent's version was different. It was not rebellion. It was refinement. The jacket had a shawl collar in silk satin, the trousers sat at the natural waist, and the whole thing required nothing underneath but skin and confidence. Catroux wore hers to dinner at Maxim's. The maître d' refused her entry. She went elsewhere. By 1967, every woman who mattered owned one.

Loulou de la Falaise and the atelier

If Catroux was the silhouette, Loulou de la Falaise was the colour. She arrived at Saint Laurent in 1972, the daughter of a French count and an Anglo-Irish model, already fluent in the language of scarves, brooches, and the precise disorder of too many rings on one hand. Saint Laurent hired her to design jewellery. What she actually did was live inside his collections.

De la Falaise understood something most stylists miss: that a look is not complete until it is slightly undone. A belt worn backwards. A jacket over bare shoulders. Earrings that did not match. She worked in the atelier on rue Spontini, where fabric was draped directly on the body rather than drafted on paper, and her influence was everywhere. The 1976 Russian collection—those quilted coats, the fur hats, the embroidered blouses—came from her childhood memories of her grandmother's wardrobe. The gypsy skirts and peasant blouses of the late seventies carried her fingerprints in every mismatched print.

Saint Laurent once said she was his right and left hand. What he meant was that she could finish his sentences. When he designed a black crêpe evening gown, she added the amber beads. When he sent a model down the runway in a blazer, she rolled the sleeves. She did not follow trends because she had no use for them. She wore Balenciaga couture with a flea-market belt and made both look inevitable.

Her jewellery for the house—bold Maltese crosses, Byzantine cuffs, resin bangles the size of napkin rings—sold in the thousands. Women bought them not because they were expensive (they were not), but because they looked like something stolen from an interesting grandmother. De la Falaise stayed with Saint Laurent for thirty years. When she died in 2011, Anna Wintour called her the chicest woman who ever lived. She was not wrong.

Catherine Deneuve and the customer

Catherine Deneuve met Yves Saint Laurent in 1965, the year she filmed Repulsion. She was twenty-one, already famous, already beautiful in the way that made casting directors lazy. Saint Laurent dressed her for Belle de Jour in 1967: those patent Vivier pilgrim pumps, the double-breasted coat, the severe bob that turned her into a cipher. The film made her a star. The clothes made her a client.

Deneuve was not a muse in the studio sense. She did not drape fabric or suggest hemlines. What she did was buy the clothes—couture and ready-to-wear—and wear them in public for forty years. She understood what Saint Laurent was selling, which was not fantasy but a version of adulthood that did not require suffering. A good coat, a clean shirt, trousers that fit. Deneuve wore his safari jackets to film sets, his evening trousers to Cannes, his blazers to the Élysée. She looked, always, like a woman who had better things to do than worry about her outfit.

Saint Laurent designed her wedding dress in 1965 (she married the photographer David Bailey; it lasted four years). He dressed her for the cover of Vogue in 1968, 1975, 1983, and 1992. When he retired in 2002, she sat in the front row wearing a black tuxedo from the final collection. The message was clear: this is not nostalgia, this is my wardrobe.

What Deneuve gave Saint Laurent was proof that his clothes worked outside the studio. She was not a socialite or a bohemian. She was an actress with a career, a mother, a woman who appeared in public fifty times a year and needed to look like herself. The fact that "herself" was defined by Saint Laurent's tailoring was the point. She bought the clothes because they worked. That they also happened to be beautiful was incidental.

What they built

Saint Laurent's genius was not in invention. Chanel invented the suit. Dior invented the New Look. What Saint Laurent did was take the language of menswear—the structure, the restraint, the assumption that clothing should serve the wearer rather than the other way around—and offer it to women without apology.

Catroux, de la Falaise, and Deneuve were not interchangeable. Catroux was androgynous, de la Falaise was maximalist, Deneuve was controlled. What they shared was an understanding that Saint Laurent's clothes were not about transformation. They were about recognition. You did not put on a Le Smoking to become someone else. You put it on to become more yourself.

The maison today, under Anthony Vaccarello, still mines that archive. The tuxedos return every season. The safari jackets. The blouses. What made them relevant in 1966 is what makes them relevant now: they are not fashion, they are clothes. And the women who wore them first knew the difference.