A backstage drama at the National

Last night the National Theatre staged the first night of a revival of Michael Frayn's Noises Off. In the words of the National's publicity material, it is a farce about a theatre company that "stumbles from dress rehearsal to disastrous last night... everything that can go wrong does, as the cast desperately try to hang on to their lines, their performances and the furniture, resulting in a terrifying descent into chaos".

Last night the National Theatre staged the first night of a revival of Michael Frayn's Noises Off. In the words of the National's publicity material, it is a farce about a theatre company that "stumbles from dress rehearsal to disastrous last night... everything that can go wrong does, as the cast desperately try to hang on to their lines, their performances and the furniture, resulting in a terrifying descent into chaos".

At the National Theatre this week that must sound alarmingly close to home.

Tuesday saw the first night of a new production of Romeo and Juliet. It was directed by Tim Supple. Only it wasn't quite. The National's artistic director Trevor Nunn had stepped in during the final rehearsals to redirect the play with a chastened Supple sitting at his side.

Mr Nunn, alarmed as the bad publicity began to break, put out a statement saying that he had just been "fine-tuning" the production, because Supple had to spend time producing another play in Bromley.

That rather begs the question of why a director of a play at Britain's National Theatre is allowed to double book, working on a different production in a different place during the final days before his first night. It also conveniently leaves out the fact that Romeo and Juliet had been previewing before paying audiences at the National Theatre as far back as the start of September. Surely someone should have noticed there was something wrong back then.

The late intervention - with consequent cancellations of other previews - could cost the National Theatre up to £100,000. The cack-handed approach has certainly cost Supple his dignity.

But posterity should be grateful. Nunn and Supple have bequeathed a phrase to the world of theatre. As a number of wags have pointed out, henceforth "working on a production in Bromley" will be the theatrical equivalent of a politician "spending more time with his family".

In the event, Nunn's fine tuning doesn't seem to have been fine enough. Some papers, including this one, found things to admire in the production; but there were also some vicious brickbats with London's Evening Standard saying "you can't fine-tune a vehicle that's not really roadworthy." Worse, the problems at the National set the agenda for most of the reviews, with Bromley getting more mentions than Verona.

Trevor Nunn could be forgiven for thinking that he is more sinned against than sinning. It is, after all, the artistic director's job to keep an eye on productions in the building and help them out if they don't seem to be working. This was something he failed to do with Sean Mathias's awful, ill-starred production of Antony and Cleopatra starring Helen Mirren and Alan Rickman, and the National was rightly criticised at the time. Nunn's fault with Romeo and Juliet is not that he interfered, but that he interfered too late.

The events of this week are a symptom of deeper problems at the National. Some may be of Nunn's making; some certainly are not. The decision by artistic directors of subsidised companies on how much leeway to give outside directors of individual productions is a difficult one. As Nunn's predecessor Sir Richard Eyre told BBC Radio 4's Front Row this week: "In the subsidised theatre you give artistic freedom. With a commercial production you would think, 'we're losing money, we've got to get someone in to fix it'."

But an audience at a subsidised venue is entitled to see a "finely-tuned" production just as much as an audience at a commercial theatre. If Trevor Nunn is making it known, however coyly, that as artistic director he must see that every production reaches the highest standards, regardless of whose feelings get hurt in the process, then about time too. He should have done it earlier, especially after Supple's last NT production The Villain's Opera lost money and was critically panned.

Yes, he has made some bad decisions on new plays, and at the National you are not allowed to forget. Nunn's choice of the execrable Sleep With Me by Hanif Kureishi made critics question his new plays policy for months to come.

But he can also point to unforgettably exhilarating moments in his regime. The electrifying premiÿre of a "lost" Tennessee Williams play Not About Nightingales, the overdue creation of an ensemble company which won consistent rave reviews, awards for Summerfolk and the Merchant of Venice are all major achievements. And the critics who pillory him for directing musicals - Oklahoma! last year, My Fair Lady next year -- show a curious snobbery about an utterly valid theatrical form, enhanced by the top talent and generous rehearsal time available at the National. Behind the scenes he has also made some effort to widen the National's audience by putting on street theatre and concerts outside the building.

But if Nunn has brought to the National his own indubitably great talent, he has also brought a great ego. Alone among the artistic directors since Laurence Olivier founded the institution, he has decided not to have any associate directors. Sir Peter Hall had several theatre directors to advise him as well as playwrights such as Harold Pinter to help in choice of plays. The job is too big for one person. Nunn must learn to share. The need is perhaps greater now than ever with ennobled executive director and head of the production side, Genista McIntosh, having to spend time in the House of Lords.

Matt Wolf, London theatre critic for Variety, says: "There is no doubt that Trevor Nunn is one of the great directors in the English-speaking theatre; but that's not the same as being a world class producer. One applauds his own work at the National and over the preceding years, but he must not be seen to be a one-man band."

This is echoed by senior insiders at the NT, who continue to wonder why he is not finding new young directors. "Where is the next Deborah Warner?" said one. "Trevor needs to be finding the new talents and encouraging them." Other say he must also learn to love budgets - finance directors tend not to get the hugs that he gives to actors. The NT's finance director Lou Hodges left earlier this year, apparently after budgetary clashes with Nunn.

Trevor Nunn's contract ends in 2002, by which time he will be 62. Some of the applicants last time around, Jude Kelly from the West Yorkshire Playhouse, Stephen Daldry late of the Royal Court and now of tinseltown, may well be interested again. Both of those would usher in a lively period. Sam Mendes, much touted, is understood not to be interested. But NT chairman Sir Christopher Hogg and his board are believed to be minded to appoint Nunn for a second term.

If Nunn can begin to make clear to the public, to his staff and to himself precisely what the role of an artistic director is, and brings in new directors to help him shoulder the load, it could yet be an invigorating second term, and the board's likely decision the right one.

Had Nunn stated early in his reign at the National that it was a part of his job to sit in on productions - and from an early stage - and change them when he thought they weren't up to scratch, the financial losses, bad publicity and embarrassment of the last week could have been avoided.