THEATRE The Odd Couple, Haymarket Theatre

After 30 years, Tony Randall and Jack Klugman know their roles inside out. The trouble is, they've aged but their creations haven't.

Neil Simon is an American institution.You will search the West End in vain for anything named after Alan Ayckbourn, but Broadway boasts the Neil Simon Theatre (250 West 52nd St, since you ask). He is his country's most successful and prolific living dramatist, with innumerable plays, films and the odd musical to his credit. His career has consisted of a highwire act, balancing acerbity and sentimentality with a masterly use of the one-liner. He has, of course, fallen off a few times, but the Tony award for The Odd Couple in 1965 set an early seal on his career.

It's no surprise that the show spawned a movie and a TV sitcom. The play itself, down to its strangely inconclusive ending, feels like the pilot for a series and whatever you think of Simon's tendency to force character to fit the lines, this is great comedy in an instantly recognisable situation. Slung out by his wife, fearsomely fastidious Felix pitches up on poker night at the home of his oldest friend Oscar, one of the highest paid sportswriters on the East Coast and champion slob, and ends up staying.

The piece is so indestructible that it survived a gender-swap in a recent production but there is no such rethinking here. Aside from the odd adjustment taking account of cultural "advances" such as McDonald's, Harvey Medlinsky's revival works on the principle that familiarity breeds contentment. This means having the theme tune to the long-running TV series throughout the evening, plus its stars, Tony Randall and Jack Klugman (who replaced Walter Matthau, for whom the part was written, on Broadway). The pair of them know the characters inside out but at the risk of being ageist, this is a mid-life crisis comedy. Hearing about the collapse of 12-year marriages and estranged young kids from these veterans is peculiar. Felix's hypochondriacal physical ailments should be funny character points. Here they come across as slight exaggerations in a man whose body is justifiably beginning to show signs of wear and tear.

Owing to major surgery on his vocal cords, Klugman is forced to use a head-mike to make himself audible. The gloriously disgruntled character is there in spades, but struggling to hear him tightens you up. All you want to do is relax, sit back and laugh at the gags that arrive at a staggering hit rate, but Simon's comic rhythms are disturbed and, alas, the punch is pulled.

Things get worse with the arrival of the "coo-coo Pigeon sisters", two giggling English gels who might as well wear a banner announcing "sex interest". Suddenly the play shows its age. We haven't seen characters like this since There's a Girl in My Soup, and, lusted after by men old enough to be their fathers, it all turns queasy. Master farceur Henry McGee is on tremendous, exasperated form but this stands and falls by its stars. They're snappy and funny, but by the end we should be hysterical not nostalgic.

At the Theatre Royal, Haymarket, SW1 to 12 Oct. 0171-930 8800