It takes a lot to shock the fashion world, but the breakup of the power couple behind Zadig & Voltaire managed to do it. The global French brand, known for the edgy clothes and accessories carried at more than 300 directly owned boutiques around the world, is run by C.E.O. and founder Thierry Gillier and artistic director Cecilia Bönström, whom he hired as an assistant in 2003 and reportedly wed in 2016. But now that Gillier is allegedly coupled with Cecilia’s twin sister, Charlotte, things are a little compliqué. (Charlotte could not be reached for comment.)

After two decades of marriage, Charlotte Bönström is in the process of divorcing her husband, Vittorio Assaf, the New York restaurateur who owns the chain of Serafina restaurants with his partner, Fabio Granato. Assaf has denied reports that he and Cecilia have coupled up. “It is very difficult,” Assaf told the New York Post’s “Page Six.” “But I have nothing to do with the sister of Charlotte.” How did these two charmed couples go so awry?