The communal delight that welled up at Junya Watanabe's show was a bit like the surge of elation that comes when the pieces of an impossible puzzle click together. How to make the heritage of haute couture relevant today? Where does Victoriana fit into that picture? And where have all the casual clothes gone? These questions have been swirling around Paris fashion like the sleet in the streets. And suddenly, they all settled into a moment of charming clarity under Watanabe's roof.

Girls in tufted, rough-hewn Davy Crockett hats began walking out wearing full-skirt fifties dresses in mohair plaid—part prom, part rock 'n' roll. One had a black vinyl bodice, introducing the masterfully simple melding of old-world fabric and high-tech utility Watanabe calls "heavy-duty couture." The idea came together in a series of blousons and parkas in which an outer layer of tweed was fused onto a shiny synthetic inner shell. An absolutely practical padded checked brown tweed jacket, its generous collar lined in orange nylon, bubbled into a voluminous parallel of Cristobal Balenciaga's tailoring.

Other pieces, bunched up below the waist with parachute ripcords to give a vague sense of the eighteenth century, moved toward the modernist romance that marks Watanabe's most inspired shows. Black high-neck, pie-frilled Victorian blouses and ruffle-sleeve jackets, worn with circle skirts (one padded like a nylon duvet), connected brilliantly with the sober, governessy silhouette that is cropping up as a new direction this week. Watanabe conflates all these complex influences into clothes that look current and simple to wear—and that's a stroke of genius.