Lady Windermere's Fan, Haymarket Theatre Royal, London

Some newspapers use star ratings; others have smiling or frowning theatre masks; but I would like to suggest a new, quick-glimpse device: the nail-bite rating. And it's so simple: it's a photo of my hands before and after the show. If it's a real stinker, I'll have reduced three or four nails to bleeding stumps for want of something better to do; if it's a corker, my fingertips will be untouched. The basic rule of thumb (sorry) is that the greater the boredom, the worse the nail-biting.

But to see what I thought of Lady Windermere would require more perspicacity than usual. You might see the odd little nibble there on the third finger, but the rest of the hand left completely untouched, and then suddenly there'll be a wholly unexpected blitzkrieg on the opposite index finger. It's that kind of show – flashes of clarity followed by long, creaky exposition. There's a marvellously choreographed ball scene that is succeeded by a flat, over-stated scene telling us what we already know. The classic all-chaps-alone comic scene ("gutter but stars", "price of everything, value of nothing") is genuinely funny, but then suddenly there's another pontificating duologue and you find you're nibbling again.

To whom the credit and to whom the blame? Wilde or Hall – who but Sir Peter has the clout and determination to put a play such as this back into the Theatre Royal Haymarket? – or his cast? OK, Oscar gets the blame for the naff what-I'm-about-to-do asides but the actors seem to make them naffer still. And what about the conversational longeurs, the speeches crying out to be interrupted, the motionless poses? They are played very straightforwardly, often motionless, without any attempt at interruption or stage business, so their success hinges on how much personality each character can bring to the party.

Jack Davenport, as Darlington, brings his standard slouchy, squealy, slick-haired passion and it works, giving him a motor to speed through the wordiness. But Joely Richardson, as the eponymous object of his passion, starts the evening as though she is teaching English as a foreign language. As the evening progresses, she warms up, but never truly convinces: everything seems more like mannerism rather than belief, head-shakes rather than agonies, and her near face-slap of Mrs Erlynne looks more like an elimination round in the World Stare-Out Championship.

And what hope for the big surprise that Mrs Erlynne is actually Lady Windermere's (disgraced, supposed dead) mum when the role is played by Joely's (real-life) mum? I can't believe many new readers aren't going to make this leap well ahead of time, but it doesn't matter. Vanessa Redgrave simply brings to bear her luminous eyes and you can understand why women believe in her and men adore her – even her compliments seem to be composed of mixed layers of irony and sex.

All the comic buffers do their bit unstintingly, so Googie Withers and John McCallum and Roger Hammond will all be mentioned in dispatches. As a result, there's plenty to enjoy in this production, nothing to surprise you and just a little too much to underwhelm. So you can see why you'll need a careful examination of my nails.

Booking to 8 June (0870 9013356)