Olivier Theyskens describes his role at Rochas as acting "like a hinge between past and present." That image helped explain the video projection of butterflies, opening and closing their multicolored wings, that played as a backdrop to his fall show—visuals that alluded to the fragile femininity and evanescent color that is emerging, slowly and methodically, from the chrysalis of this long-slumbering Parisian house.

The renewed look of Rochas has taken shape according to a fifties-couture template. Sculpting his silhouette around the idea of tiny bolero jackets and belled skirts, Theyskens has added his own, next-generation fascination with the structure of old-world underpinnings. Small suits and coats, often cut with curving volume in back, were interspersed with corset-dresses and flounced skirts made of the sheer, stiff crin that once formed the unseen underlayers of haute couture. "It's really interesting that modern fabrics can evoke these old constructions," he said. "But now we can use techniques like laser cutting, and that can make it better than the original."

Theyskens moved the collection forward by sending out his girls in not-so-demure pointy metallic high-heel pumps in candy wrapper-bright turquoise, violet, green, and cherry red. A touch of fluidity and draping turned up in silk camisoles—loose at the breast, tucked into skirts at the back—to create new, bloused, flyaway volumes. As a contrast, his new coat shape, a molded couture duffel, came fastened with "hinge" toggles. In all, this collection was a concise, measured development of the brand-building look Theyskens has been working since he joined the house.