The good thing about having an event the night after the Met gala is that everyone is still in town. The bad part is that the "Party of the Year" can leave even the most devoted night owl a little worse for wear. "I was nervous people would be hungover today," Marni's Consuelo Castiglioni said at her Upper East Side store opening. "But I think everyone looks great." Thakoon Panichgul admitted he wasn't feeling quite 100 percent, but he brought along a pick-me-up: his new Yorkshire terrier/Chihuahua mix puppy, Stevie (after Stevie Nicks).

Around the corner on Madison, Brit jewelry designer Solange Azagury-Partridge celebrated her own new boutique. "It's like a jewel box," she said, pointing out the black velvet walls, the gilded display cases, and the light-up Swarovski crystals, which form constellations on the ceiling. The decor wasn't the only thing that was glittering. Several of the guests wore Azagury-Partridge's diamond "Witchy" rings, so called because that is the jeweler's nickname. "She's a good witch," said her pal, the actress Rachel Weisz. Toward the end of the fête, things got steamy in the jewel box, prompting Yasmin LeBon and current Solange campaign girl Susie Bick, among others, to spill out onto the sidewalk. Which was convenient: It was already time to head to the post-party dinner a few blocks up the street at the Carlyle's Bemelmans bar, where Weisz soon ditched her heels and joined in some high-energy group dancing.

— Derek Blasberg