But mostly owing to the testosterone-free environs. Women-only clubs are on the rise.
"There’s been a paradigm shift, which means that, increasingly, women are seeking out other women’s company," says Percival. "It’s not that they don’t love their husbands and partners, but they often have deeper conversation with women than men."
"Women spend their lives multi-tasking, always putting family and work before their own health," adds Percival. "They are bad at actually making time to take stock, usually feeling guilty about having 'me' time and giving themselves breathing space.
"Grace was created to put the best of the best under one roof. I wanted to create a place where women could come and feel cared for and be intellectually stimulated."
Members come to socialize and attend events. Sir Richard Branson’s mother, Eve, gave a talk recently, as did Naomi Wolf.
But most are drawn by the spa, gym, restaurant, lounge, food delivery service (for $60 a day you can have vegan delights on tap), the services of a celebrity hair stylist and a medical center headed by apothecary to the Queen, Dr. Tim Evans.
I’m greeted by an "Angel" -- every client has her own, a cross between a personal assistant and a shoulder to cry on.
She's sweet, American, elegant in a white blouse and black skirt, looks fresh out of college, but later, I learn, has worked for a hedge fund and studied for a Masters in Art Business at Sotheby’s Institute of Art.
Even the help is a cut above.
She sits me down and hovers over me while I sign a confidentiality agreement, so I can’t name-drop about members.
Then I'm whisked around for a tour of the premises.
We walk through an immaculate atrium, lined with expensive art. The artist on display when I visit is Ewa Batchelier and her paintings can be bought for around $5,300 each.
The therapists use high-end and organic beauty brands, like ila, the holy grail of holistic treatment junkies.
On the "Massage by Our Masters" list, there's something called Integrative therapy and it costs $1,500 for 240 minutes.
I’m pointed in the direction of an anti-ageing Henri Chenot facial ($219 for an hour) and the therapist is a sweetie, no airs or graces.
I emerge an hour later, floating.
The Medical Centre, the one bit of the club open to non-members, is impressive.
Among the roster of experts on call are a cardiologist, dermatologist, nutritionist, psychotherapist, plastic surgeon, acupuncturist and women’s health therapist.
"The club is for impressive women who recognize that they’re fallible and need support; it’s not for spoilt women who are looking for a place to have lunch," says Percival. "I want these women to leave their egos at the door and be nurtured by the space and facilities that Grace offers."
Females who work in law, banking, art, media, medicine, telecommunications and fashion are among the club’s members. No footballers’ wives here.
The majority are Brits, followed by American and Italians.
So, hard luck fellas, you’ll have to head elsewhere for your modern metrosexual needs.
Grace Belgravia, 11C W. Halkin St., London; +44 (0) 207 235 8900