A short while after arriving at Shumi - after having been ignored by two sets of receptionists, been seated at a table beneath which were scattered shards of broken glass, and being moved to another - I was approached by a thin, suited man with an orange perma-tan. He was tall, had the posture of a praying mantis and wore shimmering blue reflective wrapround shades, which he did not have the good grace to remove before talking to me. He leant down and said, 'Welcome to Shumi. I hope your experience is...' Then he stood up and walked away.

You hope my experience is... what, exactly? Over soon? Not too psychologically damaging? Or maybe it was just a moment of Cartesian philosophising on the part of a restaurateur who now recognised he had opened one of the most irritating restaurants in London dining history. He simply wanted my time there to 'be'; for it not to engender any response at all. To which I can say: no chance mate.

Ah, Shumi, how do I hate thee? I hate the meeters and greeters who run around trying not to catch your eye. I hate the battered old escalators which look like hand-me-downs from the Elephant & Castle shopping centre. I hate the nasty decor and I hate the asphyxiating prices. But most of all I hate the concept.

Shumi is a Japanese restaurant serving Italian food. Or an Italian restaurant where the food is served Japanese style. So you get to eat risotto with chopsticks. Hurrah! That's an idea we've been waiting for, isn't it? There's also a 'paccio bar', where 'Italian sushi' is prepared, by which they mean carpaccios of meat or fish. 'The tastes that you will experience will be typically Italian,' says a press release, 'but you may find that we have taken an Eastern road to get there.' Now I get it. You thought this up during a booze-fuelled bender down the A13 to Southend.

The only way Shumi might have worked is if the food were truly exceptional, but it isn't. The best I can say is, it isn't offensive. Fragile slices of beef dressed with olive oil were fine. A 'mosaic' of raw monkfish and tuna was less interesting than the shreds of confited aubergine that came with it. Saffron squid tasted of neither fish nor saffron. A main of roast John Dory was completely over-salted. Agro-dolce - bittersweet duck - was pleasant and nutty, but not £18-a-shot pleasant. And £5 for the Shumi Espresso plate - lukewarm coffee, a chocolate, a shot glass of vodka-drenched sorbet - was not 'pretty special', as the waitress had claimed. It was a collection of disparate objects arranged on a tray, as if for a memory test at a children's party.

Our waitress, it must be said, was sweetness itself and should be able to find less socially divisive employment, perhaps by turning to a life of crime. We asked her what Shumi meant. She said it might be Japanese for 'Hush', which is the name of the owners' other London restaurant. (One of the owners is Roger Moore's son Geoffrey, he of the orange tan.)

Our bill, without a single drop of overpriced alcohol, would have been nudging a ton, were it not for the opening week 25 per cent food discount, and I gave thanks that it was not my money. I also gave thanks for the company of my friend, who made it bearable.

Even with that saving grace I was left with this one thought: Shumi was two hours of my life that I'll never get back.

· Shumi, 23 St James's Street, London SW1 (020 7747 9380). Meal for two - anything would be too much.