British bad-boy artist Damien Hirst has a knack for drawing attention to himself, but last night at Prada's Soho Epicenter he quite literally deflected the glare onto his friend Antony Genn's band The Hours. Hanging above the makeshift stage in the center of the Rem Koolhaas-designed store was a giant, mirror-paneled skull—an imitation of the diamond-encrusted version Hirst recently sold for roughly $100 million. Sitting underneath the glorified disco ball were such head-bobbers as the Olsen twins, Zoe Kravitz, and Steven Tyler.

Following a five-song set from their album Narcissus Road, the musicians, clearly not happy with the acoustics, decamped elsewhere. But a crush of other scenesters hung around to enjoy hot dogs and potato skins and feast their eyes on the likes of Gemma Ward, Lily Donaldson, and Petra Nemcova. And the band left at least one new admirer in their wake. "I didn't know their music before," said Jeremy "Mr. Fashion Week" Piven. "But I like it."

Uptown, meanwhile, legions of Roberto Cavalli fans headed to Fifth Avenue for the opening of his Just Cavalli flagship. Jennifer Lopez, the ubiquitous Steven Tyler, and Diane Kruger were among the boldfacers who made it past the sidewalk jam into the store, which was decked out with mirrored walls and neon lights. "This is very loud," Mena Suvari said of the crammed space. "But it's also sexy, and very Cavalli."

Things were a little calmer at the post-opening dinner party at the Waverly Inn, which was packed with celebrities from Demi Moore on down—in other words, just another night at the Waverly. Said Jessica Simpson, a Cavalli chick if there ever was one: "I'm a curvy girl, and his dresses make my voluptuousness feel right."