Shy and hidden behind his over-large glasses, Yves Saint Laurent learned everything from Monsieur Dior to whom he became assistant in 1955, at the age of only 18. This young aesthete, who won the first prize in the dress category of the International Wool Secretariat competition, learned the step-by-step process of how to go from the abstract nature of the sketch to the "reality of the woman", as he explained in an interview. That same year, the American magazine Harper's Bazaar featured one of his first designs for Dior, photographed by Richard Avedon. The image of the model Dovima, aloof in a black and white evening gown, surrounded by elephants, would become famous around the world; it’s given pride of place in one of the first rooms in the exhibition. In 1957, for the Fuseau line, the last presented by Christian Dior, Yves Saint Laurent designed a fifth of the outfits. When Monsieur Dior suddenly died later that year Yves Saint Laurent was chosen to carry the torch. At 22, the "Little Prince of fashion", as the press nicknamed him, showed the 178 looks of his first collection, for spring-summer 1958, called Trapèze, in an pressured ambiance of overwhelming anticipation. In it he freed himself a little from the influence of Christian Dior and the New Look without disavowing the spirit of the House, and found his own aesthetic voice: clean lines, less focus on the waist, more defined shoulders as well as shorter dresses, in black, present throughout the exhibition. When faced with the Marilyn draped taffeta black dress with straps, the grand evening dress from 1959 with red skirt and white top decorated with a rose, or the floral-print cocktail dresses that sprinkle the itinerary, one thing becomes clear: the Yves Saint Laurent style signature is already in evidence, having blossomed in the ateliers of Avenue Montaigne. As the ultimate premonition, the young virtuoso’s last collection for Dior is called Silhouette de demain. One of his most subversive pieces is shown in the display devoted to the designer: Chicago, a mink-lined black crocodile jacket, inspired by Marlon Brando and the bad boys of the time in their black leather jackets, caused a scandal in 1960 and is today seen as an unquestionable classic.