PARIS — Late Saturday afternoon and the entire United Nations of fashion was filing dutifully into the Brutalist concrete building that is the Russian Embassy here.

In they went, past the model of St. Basil’s Cathedral in Moscow; up they went on the grand red-carpeted staircase. Down they sat under the crystal chandeliers. Patiently they waited, to see what would happen next.

“Only Rei Kawakubo could get so many Americans into the Russian embassy at once,” one guest said. Well, what do you do as a next act after a season in which you became only the second living designer to ever have a solo exhibit at the Metropolitan Museum of Art’s Costume Institute?