Last night's Zac Posen afterparty—an intimate affair for nearly a thousand of the designer's closest friends—had a decidedly work-in-progress feel to it. The fete was held at the new club Mansion, which is slated to officially open tonight—and if yesterday is any indication, there's still some work to be done. As the soiree started, eau de wet paint still permeated the air, and workers were busy installing bookshelves and a chandelier. Cirque du Soleil-style acrobats perilously suspended from the ceiling wowed the crowd, and go-go dancers in outfits channeling J. Lo circa 1993 provided a nod to the nightclub's lineage (its sister location is Mansion in Miami).

Everybody managed to have fun anyway—especially Tinsley Mortimer and a sequin-bedecked Richie Rich, who danced a deux on a banquette. The Tinz confessed they didn't make it to Zac's show (Tommy Hilfiger, apparently, took precedence) but cheerfully pointed out that she was sporting a Posen frock.

Later, friends and I headed to Beatrice Inn, which was steadily filling up with fashionistas until around 12:45, when undercover cops shut the place down. One escorted a leggy, young looking model out the door. Youth can get you most places in New York, but sometimes the law does catch up... at least every now and then.