Nobu Berkeley, London W1

Nobu hasn't got where it is today by launching restaurants that aren't ready to be reviewed on the opening night. The staff will have been meticulously drilled, the menu perfected, the last detail of the interior polished up by London's top restaurant designer David Collins, and the launch party obligingly attended by co-owner Robert De Niro.

Nobu, in short, is critic-proof. The "new-style" Japanese cooking pioneered by the group's presiding genius Nobu Matsuhisa may have become a widely imitated cliché, but the original Nobu in Park Lane is still regularly mentioned as one of the best restaurants in London, eight years after opening. Trouble is, it's bloody hard for civilians (ie. anyone who isn't Liz Hurley) to get a table.

To their credit, the group's owners have designated this latest Mayfair branch a no-bookings zone. Parties of six-plus can reserve a table, but otherwise it's turn up and chance your luck, and too bad if the paparazzi at the door jeer when you get turned away.

The former Mayfair Club (which sounds Bertie Woosterish, but was known for its podium dancers) has been redesigned by the talented Mr Collins. Where before the interior was a bit Donatella tacky, it has now gone tastefully Seventies futurist, all Pierre Cardin streamlined curves and tree-like excrescences.

The bar staff are a Helmut Newton fantasy made flesh; an army of ravishing, sexy hostesses who slink around in spike heels and black halterneck dresses slashed to the thigh, and crouch geisha-like at the table to take your order. Equally eye-popping are the prices - £12 for the cheapest glass of champagne and £10.50 for a cocktail. The first-night clientele - mainly Cat Deeley blondes and swaggery men of rapacious mien - obviously didn't care; they couldn't have looked more pleased with themselves if they'd been in Studio 54 on the night Bianca Jagger rode in on a white horse.

Upstairs in the restaurant, the staff greet you with Nobu's trademark chorus of "irashaimase", delivered with enough oomph to make one of my guests yelp, "What the hell was that?" Up here, the waiting staff are kitted out in designer chav outfits; a reworking of the black tracksuit, with Adidas-style stripes down the arms. Nobu's waiters tend to be well-informed, and ours was discreetly helpful in guiding us through the menu, a document no less strange and thrilling than it seemed when the Park Lane branch opened back in the last century. Unusually, in these times of restless innovation, the various Nobus offer an unchanging repertoire of dishes: sushi and sashimi, tempura, interesting salads, and hot dishes, including the famed black cod in miso. This branch introduces a couple of new elements - a Japanese wood-burning oven and hibachi table, where food is cooked in front of the diners.

Our meal combined sure-fire hits with a few of the newly introduced dishes. First up, a Nobu classic: rock shrimp tempura, sweet nuggets of shrimp sealed inside the crispest of batters, and served with a ponzu (Japanese citrus and soy) dipping sauce. Next, a sushi selection, best of which were the temaki, hand-rolled cones filled with eel and cucumber. Nigiri with o-toro, a superior tuna marbled with fat, and norimaki rolls stuffed with crunchy soft-shelled crab were also fresh and fabulous. This really is some of the best sushi to be found in London (though at £2.20 to £8.50 per single piece, it doesn't come cheap).

At our waiter's suggestion we tried cabbage steak with truffles, from the wood oven. It was knock-out; the cabbage leaves oozy with truffle oil and sexy enough to send you straight to Nobu's broom cupboard. Ringing the changes on the legendary black-cod dish, we ordered another treatment of that fish, roasted skin-on in the wood oven and served with a lime and sake sauce; good, but a little on the blubbery side. Roasted jumbo shrimp came with three zingy sauces, one of them hot enough to deliver an instant trout pout. Lamb cutlets anticucho- a wonderful combination of well-aged meat and complex marinade - were another highlight.

Mr Collins' lighting is as flattering as ever, but the acoustics are shocking. When the volume rose to yelling pitch, we gave up on conversation and settled for gazing at the beautiful people. "Why do pretty women always go out with such terrible men," mused one of my companions, the comedian David Baddiel. Realising we were probably the only people there who remembered Joe Jackson's great song on that theme, we lapsed back into silence.

Puddings from a Western-leaning list included chocolate haramaki (spring rolls) and a bento box, partnering fondant chocolate cake with green-tea ice-cream. These brought our bill to just under £200 for three, a total which seemed almost thrifty under the circumstances, and was achieved only by wrestling the wine list from David and switching our order to the cheapest white, a £31.75 Sauvignon Blanc.

Nobu Berkeley isn't as cool and exclusive as the original Nobu, and the preening clientele are not people most of us would choose to spend an evening with. But when the food's as good as this, quite frankly, who cares? E

Nobu Berkeley, 15 Berkeley Street, London W1, 020-7290 9222

(reservations only taken for groups of six or more)

Food: *****
Ambience: ***
Service: ****

Meal for two, with wine, around £140

SIDE ORDERS: TURNING JAPANESE

Geisha

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Nozomi

A new Nobu rival? The Nozomi team must have faith in its address and modish cooking, and our hunger for Japanese. Sashimi, sushi and drinks upstairs; serious stuff (wagyu beef etc) below.

15 Beauchamp Place, London SW3, 020-7838 1500

wasabiSabi

From comfort food (gyoza) to finer dishes (oh look - black cod with miso) and even teppanyaki theatre (choose your ingredients and sit back for the show). Pity about the "just like Tokyo" exterior.

227A London Road, Sheffield, 0114 258 5838

Zushi

Cardiff jumped on the conveyor belt a year ago and hasn't looked back. Zushi is a slick stop-off for families and friends wanting good-value sushi, noodles and adventure (baby-squid-head nigiri).

The Aspect, 140 Queen Street, Cardiff, 02920 669911