"I've been in five cities this week," said Larry Gagosian. "So I'm ready to do it up tonight." The blue-chip art dealer had come to the right place. For the grand opening of Moscow's Center for Contemporary Culture, a cavernous space dedicated to new art, Dasha Zhukova and Roman Abramovich had spared no expense. An international swarm of artists and jet-setters—a group ranging from Charlotte Casiraghi to Jeff Koons—was treated to mountains of caviar, a 1:1 guest-to-waiter ratio, and a private concert by none other than troubled chanteuse du jour Amy Winehouse. "I think I even saw the bodyguards bobbing their heads," smiled one fan after Winehouse's stellar performance. The only reveler who didn't cut loose, it seems, was Zhukova herself. The hostess knocked back just one shot of vodka during dinner, and then only because she couldn't refuse. "I was next to Jeff Koons," the Russian beauty explained. "It would have been rude not to do a shot with Jeff Koons."

—Derek Blasberg