Fifty could change all that. The grand-luxe casino in St James’s, built in the 19th century, has undergone a multi-million-pound makeover — and its membership, based on a refreshingly honest earnings-related meritocracy, is in stark contrast to the gibberish demographic of your regular members’ club.

People under the age of 35 who have never set foot in a casino imagine them to be swishly appointed speakeasies, patronised by Euro lounge lizards in sharkskin jackets and Ursula Andress types in cocktail dresses. In reality, they are often more Harold Robbins than Ian Fleming, with a United Arab Emirates smart-casual dress code and interior design inspired by Trusthouse Forte carveries. You go looking for Casino Royale, but you get a Royale with cheese.

Fifty, though, is not your average casino. It is fast garnering a reputation as the Chelsea FC of the European gambling industry. In a bold, Abramovich-type flourish, its proprietor, London Clubs International, has signed up Robert Earl, the brains behind the Planet Hollywood chain, as the razzle-dazzle partner in this ambitious project. Earl, in turn, has brought in the architect Jeffrey Beers, renowned for the sensory overload of his interiors at “performance” eateries in Las Vegas — China Grill, Olio! and Rumjungle. There are two restaurants, Rama and V, overseen by the chef Jean-Georges Vongerichten, whose New York diners, Spice Market and Mercer Kitchen, regularly play host to Nicole Kidman and Bruce Willis. The cocktail bar employs Salvatore Calabrese, a man who has mixed martinis for Cindy Crawford, Nelson Mandela and the Queen.

“Gaming,” says Earl, “is just one element of the Fifty experience. I want to make gambling far more relaxed and less stuffy, inject a funkier feeling into the decor. The idea is that you’ll use your membership to come and eat downstairs, then perhaps go upstairs to gamble if you feel like it.” Beers says: “My intent is to create something bold and never seen before.”

If all this sounds a bit extravagant and over-the-top, then it is entirely appropriate. Earl, ever the PT Barnum of his trademark “eatertainment” industry, wants to bring a bit of decadent Las Vegas pizzazz to buttoned-up St James’s. And in Vegas, over-the-top is considered to be the model of understatement. Accordingly, there is nothing thrifty about Fifty. The refit budget is rumoured to be £7m. Laser-etched mirrors, custom-made suede wall coverings and gold-leafed capitals abound. There are white-glass chandeliers made of what looks like giant servings of frozen tagliatelle. And the basement club must be one of the most libidinous little boîtes in Europe.

David Furnish, Julien Macdonald and the models Jacquetta Wheeler and Jasmine Guinness have already paid a visit, while the Savile Row tailor Richard James launched his men’s fragrance there last year, before the refurb. “It’s always been an amazing building,” says Sean Dixon, the director of Richard James. “It had a stealth-wealth vibe that made it properly exclusive. The problem was, most people in London had never even noticed it, never mind stepped inside it.”

Getting new, younger members, acknowledge Dixon, Earl et al, will inject new life into the building. So, will Fifty fly? Will it become a hang-out for thirtysomethings? Or will the residual intimidation factor and stuffy old image remain a problem for the capital’s social elite? With a 3am drinking and dancing licence, and the gilded drama of the architecture — those huge entrance doors, that glamorous sweeping staircase, those vast floor-to-ceiling windows made of bulletproof glass — its chances have to be pretty good. Add to that the fact that the Duke of Wellington and Disraeli used to gamble here, and things are looking a lot better than 50:50 for Fifty.

Fifty: 0870 415 5050, www.fiftylondon.com

Times recommends

• It is possible to look stylish while pregnant
• Britain’s tot models
• Who and what benefits from the heat wave?