What's all this then? Essentially a private dining room, but Krug, the world's most exclusive bubblesmith, calls it 'an interpretation of the modern world of Krug'. One of only three Krug rooms in the world (the original is at the Dorchester Hotel in London; a fourth is planned for Hong Kong), it is discretely hidden away in the basement of the exclusive Restaurant Tanga, which is owned and run by genial celebrity chef Masa Nagasaka. A Krug-trained sommelier is on hand to guide you through the pricey maze of Grande Cuvee, Rose, Clos de Mesnil, Vintage and the super-rare Krug Collection, and although it's not compulsory to drink Krug in the Krug Room (right), not doing so would be akin to flying first class and requesting an economy-class meal. Where is it? It's on a back street in the Akasaka area of central Tokyo, but while suited-up Tokyo cabbies might wear white gloves and charge mortgage-level fares, there is a good chance yours won't be able to find the place. The fact that Restaurant Tanga has no exterior sign doesn't help either. Our group was deposited on the street with vigorously reassuring finality (followed by a heavy foot on the gas) but we were still two blocks from the actual location. Take the phone number and they'll come and get you if you're within walking distance, but before that, have your hotel concierge staple detailed instructions to your taxi driver's forehead. Luxurious or basic? A bit of both. The mood is exclusive and discreet, with a private hidden lift and a private toilet offering no fewer than 25 types of individually packaged, palate-refreshing water, but the single-table dining area is fashioned from basic-but-classy hardwood and marble. The most conspicuous feature is a sink with one tap, which may be for some obscure traditional Krugerian ritual, but wasn't used while we were there. What's on the menu? The cuisine is French with just a hint of Japanese, but you can have pretty much anything you like; Nagasaka takes careful aim to please. Tutored under the weighty rolling pin of the renowned Wolfgang Puck, he's one of an extremely rare breed: a chef long on talent but short on self-importance. What's the bottom line? That depends on how much champers you put away, but the three degustation menus, although worth every yen, are priced from about $600 a person, rising to $1,700 a person for the more substantial Masa menu. And that's before your Krug bill. The Krug Room, Restaurant Tanga, Wakabayashi Building, 2-8-5 Akasaka, Minato-ku, Tokyo, tel: 81 3 5575 6668.