Andrew Lloyd Webber and the producer Sir Cameron Mackintosh joined former cast members for a masked ball to celebrate The Phantom of the Opera becoming the longest-running show in Broadway history.

With its 7,486th performance, the Gothic melodrama about a disfigured composer who haunts the Paris Opera and falls in love with the beautiful soprano Christine has broken the previous record set by Lloyd Webber’s Cats.

“It’s overwhelming,” the composer said. “When I saw how Cats was going I did say to all my friends, ‘You realise that something like this could not happen again’. And then, of course, Phantom happened.”

The show has become the most valuable entertainment venture of all time since its world premiere at Her Majesty’s Theatre in London in 1986. Its worldwide box office of $3.2 billion (£1.8 billion) dwarfs even the $1.2 billion (£6.7 billion) earnings of Titanic, the highest-grossing film of all time.

The musical has been seen by more than 80 million people at more than 65,000 performances in 119 cities in 24 countries. It is now playing in London, New York, Budapest, Tokyo, São Paulo and Essen, with new productions planned in Taipei and Las Vegas.

Lloyd Webber conceived the show when he came upon a copy of Gaston Leroux’s 1911 potboiler novel while browsing at a bookstall on Fifth Avenue. He was struck by its final lines in which the Phantom’s body is exhumed and Christine’s ring found on his finger.

Explaining its success, the composer said that audiences liked to find themselves in “an escapist, romantic world”.

Propelled by its West End success, Phantom opened at the Majestic Theatre on Broadway on January 26, 1988, with a record $18 million in advance ticket sales. Although some critics were less than impressed, the production won seven Tony Awards, including Best Musical and Best Actor for its star, Michael Crawford. Since then, almost 11 million people have seen the Broadway show.

The current Phantom, Howard McGillin — now in his second stint — is the longest-serving of the 11 actors to take the role, with more than 14,000 performances to his name Crawford was among the guests at the lavish masked ball at the Waldorf Astoria that echoed a famous scene in the show. But his original co-star, Sarah Brightman, did not attend because of recording commitments.

Click here for film news, reviews and listings

MUSICAL NUMBERS

7,486 performances

930 weeks

7 Tony Awards

11 million theatregoers

$600 million ticket sales

11 Phantoms

3 original actors in show

476 miles travelled by the falling chandelier

1,424,250 quarter teaspoons of shot powder used

6,899 ounces of liquid fog

Times Recommends

• 'Great Schlep' may seal deal for Obama
• Hindu 'storm troopers' flex their muscles
• Ahtisaari: deserved reward for (failed) plan