THE harpy on the desk where I picked up our tickets for Zumanity, the latest adults-only show in Las Vegas, glared at me above her specs. “You do realise,” she barked, “that you have to be 18 to see this show. It contains naked bodies and strong language.”

“Can’t wait, dear,” I shouted back, to not even a titter from her, or anyone else in the queue at New York-New York, the hotel on the famed Strip which hosts Cirque du Soleil’s newest show, claiming to “awake primal urges to a new form of eroticism”.

Still, it proved two things: our American cousins still don’t get British humour, and Vegas has swung back to Sin City mode after unsuccessfully trying to reinvent itself as a family resort.

It could just be me, but I felt no primal stirrings, just irritation at being showered with black crepe paper confetti. Erotic? I don’t think so. The show moves fast — imagine the Folies Bergère on speed — with wild gyrating and much use of spray-on body stockings to emulate flesh. The only nudity was a cheesy male stripper who hid his embarrassment with a large bunch of roses. Give me O, the Cirque’s polished and outstandingly original water ballet with acrobatics, any day.

Cruising the Strip, always as neat as a Swiss railway station (who moves the litter?), it’s obvious that Vegas is still a city where sex sells. Billboards and taxi hoardings are bulging with tanned breasts and buttocks and sad-looking creatures — you can’t really call them pimps — do 24-hour shifts handing out leaflets for prostitutes, wearing T-shirts proclaiming “Naked girls s traight to your room”.

But beyond the sleaze there’s a new, sleek Vegas that wears the rosy glow of wealth. Allegedly up to a third of the city’s annual 35 million visitors don’t gamble. At night they do the shows, by day they top up their Botox in world-class spas, sip cocktails by the pool, or go designer shopping. The usual suspects — Tiffany’s, Dior, Chanel, Gucci, Prada and Versace — make more profit per square foot in Vegas than in any of the world’s capitals.

This means that today’s Vegas is thicker with Wall Street types in Armani than rhinestone cowgirls with bull-neck boyfriends. Much of the credit for the makeover goes to entrepreneur and fine art collector Steve Wynn, owner of the five-star Bellagio, the smartest address on the Strip, and the £1.5 billion Wynn Las Vegas which opens next year.

Wynn has even managed to introduce culture to a surprisingly receptive audience. The Monet exhibition, showing at Bellagio, and other Impressionists on loan from the Guggenheim at the Venetian, offer a sophisticated alternative when the chips are down. “Steve has single-handedly reinvented Las Vegas,” one of his many acolytes told me. “It used to be a dirty weekend, now it’s a luxury break.”

What Vegas has never been noted for is the quality of its food. But a new clutch of restaurants has emerged to confound the traditionally snooty gastronomic world.

“It’s amazing,” says Sandy Zanella, PR manager of MGM hotels. “In six years we’ve gone from buffet central to some of the best restaurants in the US. All the top chefs from New York, Boston and San Francisco are coming here and their restaurants are booked out every night.”

At Picasso in Bellagio, named for the boggling originals hung on the walls, thanks to Wynn again, we discovered an ultra-smart, designer-clad crowd. Here, master chef Julian Serrano produced an exquisite seven-course menu, a steal at £53 a head, which included poached oysters with oscietre caviar, black bass with saffron sauce and pigeon with wild rice risotto. It competes with Le Cirque, also part of the Wynn empire, a spin-off from the New York gustatory temple, for the accolade of best restaurant in town.

But for food as theatre, against a metro chic backdrop of blond wood, etched glass sculptures and indoor rain-shower fountains, it has to be Aureole in the Mandalay Bay Hotel, brought to Vegas recently by Charlie Palmer, New York’s equivalent of Gordon Ramsay. Here, the wine list is an electronic notebook delivered to your table by a cool-suited sommelier, skilled in finding his way around one of the world’s biggest and most impressive cellars.

Make your choice and he’ll ping one of the “wine angels”, a woman (gorgeous, naturally) who will be hoisted electronically in a harness up the 42ft glass-and-steel wine tower to select your bottle, abseiling down to deliver it.

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