"Going to a club used to be like going to hell for a night and coming back," Sardinian photographer Sebastian Piras tells me as he looks around Le Bain, the Standard hotel's new rooftop lounge. And now? "Now, with the new laws..." he trails off. "There's a lot of rubbernecking." We're at a party hosted by Dree Hemingway in celebration of a new Ferragamo fragrance called Attimo, which means "instant" in Italian. The Instant is also the name of the night's signature cocktail, a sugary mixture of St-Germain and rosť topped with a floating pansy. I feel like a floating pansy. It's clear at a glance that this is a female-centric party, with the women in full flower and the men serving as frippery. I'm not sure whether this is the inevitable result of Bloomberg's smoking ban or the fact that we're gathered here to fête a fragrance. Still, I can see it through Piras' eyes: a room of willowy women moving the way women do when there's little male attention at stake. And he's right—insofar as I get what he means by hell.

Half the partygoers are, like Piras, European, and they all go semi-nuts when Biggie's "Hypnotize" comes on. Maybe it's an instinctive Continental response to the lyrics about Moschino, Versace, sex in expensive cars. (Couldn't be the Brooklyn-basement part.) I loop around the room to ask Dree about her plans for the summer. "Italy," she tells me. And then she changes her mind. "Well, actually no. I'm going to Idaho, where I grew up." She turns to a friend and clarifies. "I'm going to the Italian Riviera." Puzzling. There's a gasp and someone behind me says, "OMG is that Ted Danson?" It's not.

The trajectory of the party is upward, in the direction of the roof, so up I go—ascending directly into the sight line of Stavros Niarchos. He gives me a cutting look; maybe he has a press antenna. Then again, maybe not: Moments later the Greek shipping heir is chatting up a PR girl possessed of an oddly enchanting simian beauty reminiscent of his ex-girlfriend, Mary-Kate Olsen. The roof looks not unlike a Mario Kart course: AstroTurf, obstacles, funny hats, money. Jeremy Bronson, a writer for "Late Night with Jimmy Fallon," wearing a red bow tie and Peter Sellers-style glasses, surveys the landscape sternly. "I need a real beverage," he says, and heads for the bar. I sit on a bench and start rubbernecking.

As with a Magic Eye drawing, the pattern of interest emerges from the background. Beyond the girlie scrim of activity—the Givenchy dress blowing in the wind, the models dancing to Justin Bieber's "Baby"—there are in fact men ordering manly drinks, quietly absorbing the view and ignoring trays of mini-desserts. (These are not the kind of fellows for whom free food holds native appeal.) The older ones among them wear suits, and the suits—especially Stefano Tonchi's gray number, with a white pocket square cresting above his heart—look expensive. The outfit is only part of it: Also expensive are the W editor's upright posture and attentive grooming, his subtle air of whimsy. The young men here take the opposite tack; they underdress because they can. Most of them are sporting Vans Classics—not the Spicoli checkered slip-ons but the plain canvas model that looks like a boat shoe. This was the shoe of choice for the skateboarders in my California hometown, albeit for different reasons—they're cheap and get comfortably floppy after a few dozen nosegrinds. Worn fresh, Classics will lacerate your heels with blisters. I hope these men carry Band-Aids.

At midnight everyone tramps down the hallway to the Boom Boom Room, which looks like something Melania Trump would dream up as a dressing room—all velvet upholstery and flattering lights, with views that emphasize just how far above the ground we are. The real Mary-Kate Olsen is here, not drinking, sharing a booth with Niarchos (who's ditched the PR girl) and a casually dressed man, fiftyish, who's performing a dance in his seat that is somewhere between a jig and a boxer's bob and weave. He's the one I'm looking at, the one who quickly prompts the most disgusting (and natural) question a person can ask herself at such a time: How did he get here? But the foreground recedes and the Magic Eye thing happens, and suddenly all I see are fiftyish dancing men, one at nearly every table, wearing neither John Lobb loafers nor Vans. And another question, the question of who pays for all the bottle service, suggests its own answer.

I'm reflecting on this when a Milanese banker leans in close to ask whether I need to sit down. Do I? He maneuvers me into a chair. He smells like a Ritz cracker. Do you want a drink? he asks. I shrug. Speech would encourage more leaning in. He spots my notebook. Are you writing a poem? I realize it's a joke only after I've shaken my head. Are you a mute? he asks derisively, then vanishes. The pansy drinks are gone, and all I see now are men—men in booths, men at the bar, men ignoring Bloomberg's mandate. The ratios have changed. At 2 a.m. the DJ launches into "Smells Like Teen Spirit," igniting an uproar with so many layers of irony that my processor jams. The Milanese banker is among the ones singing and shimmying along, gracefully handling a song that's awfully hard to dance to. You have to respect a man who is good at having fun.

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