You enter a serene granite-paved courtyard. Soothing acoustic music plays in the background and a gentle tropical breeze rustles the leaves of symmetrically planted bamboo, palm and rose apple trees. A softly spoken greeter dressed in flowing garb leads you through a long pergola to an oasis of indulgence in which the toughest decision of the day will be whether to take a dip in the 27-degree-heated pool, graze on a seafood platter, or allow yourself to be gently pummelled by oiled hands. Where is this chilled-out paradise? Bali? Phuket? Maldives? Try Wan Chai. After 14 months of construction, and an investment of some $100 million, Plateau opens on Monday on the 11th floor of the Grand Hyatt Hong Kong. Billed as a 'complex ... dedicated to aesthetics, relaxation, fitness and culinary', its creators claim it's the world's first residential spa development of its kind ('We don't call it a spa. Everyone does spas'). It features 23 treatment-cum-guest rooms and suites, in which you can stay overnight should you slump into a stupor after a day of intense pampering. Designed by architect John Morford, who was responsible for the spas at the Mandarin Oriental Bangkok and the Park Hyatt Tokyo (featured in Lost in Translation), the sprawling 80,000sqft development is decked out in calming combinations of mahogany granite, black marble and sassafras wood, the walls dotted with black-and-white nature photography. The clean-lined Japanese-style treatment/residential rooms (eight of which have private terraces) feature futon beds, rain showers, oversized glass-sided baths and ceramic statuary by local artist Emma Chan Suet-ha. As treatment rooms, they're spacious and indulgent, but as guest rooms, they might be on the small side for an extended stay. That said, there is more than enough space in the main areas to stretch out. Outdoors, the Zen-like courtyard offers breakfast, light snacks and cocktails, and leads to a free-form, waterfall-fed Olympic-sized pool, which has been retiled and is now heated. Poolside, there are The Grill, an alfresco restaurant, The Pool House for private functions (with a glass frontage that opens onto the pool), and a sauna with a floor-to-ceiling window through which you can see the harbour as you sweat. Back inside, the generously sized fitness area is a world away from typical soulless hotel gyms, fitted with plush black carpeting, soft lighting that's programmed to change throughout the day, and an impressive phalanx of TechnoGym equipment from Italy. A spa consultant, brought in from France, has created a menu of treatments ranging from hot stone massage ($750) to salt-and-pepper body scrubs ($650), Vichy jet showers ($725) and whitening facials ($925). 'We want to give our overseas guests a standard of experience they'd expect from the world's top resorts,' says Grand Hyatt general manager Robert Barker. 'But we also want to provide busy locals with a peaceful oasis where they can come and get away from the hustle and bustle - even if it's only for a few hours.' By the looks of things, they may well stay a bit longer. Plateau is generally open only to hotel guests (except The Grill, which is open to the public for lunch and dinner). However, visitors who book a minimum three- or five-hour programme on weekdays (from $1,625) can use the pool, sauna and fitness areas. Until March 21, rooms are available at an introductory offer of $2,600, including breakfast and a choice of manicure, scalp massage or neck and shoulder massage. Call 2584 7688 or visit www.plateau.com.hk (under construction) for more details.