CATS is well into its 16th year in the West End and Starlight Express will have its 13th birthday party in the spring.

Yet Sunset Boulevard started so full of promise back at the Adelphi Theatre in July 1993. The Strand was packed end to end with sequin dresses for the first night. It was, so the pre-show hype said, to be Sir Andrew's most adventurous, and most serious, musical to date.

Hollywood stars fought to be cast in the lead role and, after the first night, despite very mixed reviews, the advance take shot up from £2.5 million to £7 million in a day. But the musical was peppered with arguments surrounding its leading ladies and the London show needed a £1 million rejig after the first year because of problems.

The closure, so soon after the announcement that another hit musical, Tommy, is to close on Saturday, will send jitters through the West End. Sir Andrew has also decided to pull another musical of his, By Jeeves.

Sunset Boulevard has most certainly not been a flop, though Sir Andrew's staff would not say how much profit the show had made. Although Sir Andrew's argument that it was difficult to find a new leading lady to replace Petula Clark - and Elaine Page in New York - was well-made, it is hard to believe that he would not embark on the search if he was confident that the box office would hold up for another year or two.

But it has not been the huge hit that Sir Andrew has been used to with Cats, Starlight and Phantom of the Opera, now 10 years old.

"Sir Andrew has a problem," said one close associate last night. "If one of his shows doesn't run for 10 years, it's judged a flop. Sunset has been going for three-and-a-half, and any other producer would regard that as a huge hit."

Sunset was the show that almost every Hollywood star wanted - Meryl Streep thought she had got it, Shirley Maclaine said she would kill for the part and Angela Lansbury thought it was in the bag. In the end, it premiered in London with Patti LuPone in the lead.

Based on the classic 1950 Billy Wilder film of the same name, it tells the story of Norma Desmond, an ageing, sad and lonely Hollywood silent movie star, desperate to make her comeback in the Talkies.

Sir Andrew and his team, the writers Christopher Hampton and Don Black, worked on it right up until the last minute, even changing the ending with a few days to go.

Some critics raved, some thought it not up to standard. Most were agreed that the music was not memorable. Then the rows began. Miss LuPone thought she had been promised the lead when the Broadway production opened. Glenn Close, who had launched the musical in Los Angeles, got the part instead and Miss LuPone settled out of court with Sir Andrew after threatening to sue for alleged breach of contract.

Faye Dunaway was due to replace Close in the show in Los Angeles but she was removed by the producers after rehearsals on the grounds that her singing was not up to standard. She sued for defamation and alleged breach of contract. Again, the matter was settled out of court.

Then it was Close's turn for a row when it was disclosed that the box office figures in the New York production had been inflated by more than £100,000 a week while Close was on holiday and Karen Mason, her understudy was standing in. Sir Andrew admitted the inflation of the figures had been "idiotic" but refused to accept the resignation of the head of his North American operations.

This is not the end for a show that has been seen in several countries. When New York and London close, it will still be running in Melbourne and Frankfurt.

Sir Richard Eyre, head of the National Theatre, was at Sunset's first night in London. He, perhaps, got it just about right when he said then: "It may well go on for many years but . . . I don't see it becoming a classic."