Couturissime is a superlative that means “beyond couture,” and that’s where this exuberant exhibition, the first ever on the couturier Thierry Mugler, takes us. Organized as an opera in seven acts, Mugler’s designs—inspired by animals and insects, the Belle Époque and the film Belle de Jour, human folly and future fembots—are like arias with an hourglass shape. Indeed, the corset is Mugler’s working paradigm, a silhouette that reaches back to his days in the corps de ballet of the Rhin Opera, and also nods to 19th-century fashion and 20th-century fetish. —L.J.