The Andrew Lloyd Webber play "Cats" last week became London's longest running West End musical, celebrating its 3,358th performance at the New London Theatre.

"Cats," concerning the antics of alleyway felines, breaks a record of 3,357 performances of another Lloyd Webber play, "Jesus Christ Superstar," which closed in 1980."Cats" also celebrated a birthday. It opened eight years ago May 11.

Scalpers sold tickets for last week's performances for $71, twice the regular price.

The show's success has belied the doubts of investors and critics about the potential of a play based on poems about cats.

Lloyd Webber adapted the lyrics from T.S. Eliot's "Old Possum's Book of Practical Cats," but he needed to mortgage his house to keep the idea afloat.

"It was a nightmare at the time. There was so much negative reaction," Lloyd Weber told The Times of London. "People thought I was terminally barmy to try to do a song-and-dance show with a dead poet's lyrics."

Haplessness continued to dog "Cats." Eleven days before its May 11, 1981, opening, cast member Judi Dench injured a leg and backed out. Previews were extended. A bomb threat disrupted opening night.

Later the same evening, a man perched in a balcony yelled "Rubbish!" to the crowd below. Lloyd Webber admitted he was nervous the show would flop.

"It was only later we realized it was a drunk being funny about the set," he said, referring to the garbage-dump stage through which the furry performers slink.

Since its inauspicious beginning, "Cats" has been seen by 4 million people in Britain. Its worldwide gross earnings exceed $850 million, including $86.7 million in Britain, $408 million in the United States and $51 million in Canada.

Close associates said "Cats" will earn Lloyd Webber more than $10.2 million this year. The composer's Really Useful Theatre Company refused to confirm the figures.

But it is known "Cats" has made Eliot's widow a multimillionaire. Valerie Eliot earns $3.4 million a year from his cat poetry.

In the show's eight-year London run, 140 actors and actresses have passed through the feline ranks. Only one original cast member, Steven Wain, donned fur for last Friday's performance.

"I have stayed because it is such a happy show," Wain told The Times. He admitted that since being hired at 21, his life has embraced the production. He even married a former "Cats" actress.

"I suppose I will stay until I stop enjoying it," he said.

But "Cats" shows little sign of stopping. Bookings run through Dec. 31, 1999.