The culmination of New York's holiday party swirl, the Guggenheim's Young Collectors Ball is always a rambunctious affair—and this year's was no different. There were so many stars and the photographers who love them at the Giorgio Armani-sponsored event that even the most seasoned socialites were overwhelmed. "I can't see," said Olivia Chantecaille as she encountered the flashbulb glare on the museum's fifth floor, where the designer's niece and ambassador, Roberta Armani, was hosting a private dinner for the likes of Liam Neeson, Mary J. Blige, Jada Pinkett Smith, and Kim Cattrall.

The rotunda below was just as lively, temporarily transformed into a nightclub complete with an interpretive dance troupe, a mime, and the scantily clad performance artist Julie Atlas Muz. After working her way through a crowd that included Peter Som, Todd Eberle, Benjamin Cho, and Julie Gilhart, Muz took to a makeshift stage, stepped into the giant plastic bubble she had been holding in her hands, and proceeded to take off what few clothes she had on—or at least that's what this reporter was told. Asked to verify, Neeson, the tallest person in the room, confirmed it: "Yep, she's naked."

— Sarah Cristobal