NEW YORK >> Anything can happen in live theater, and audience members seeing “Beautiful,” the life story of Carole King, got a surprise when King appeared in the role of herself to celebrate the show’s fifth anniversary on Broadway.

The packed house at the Stephen Sondheim Theatre erupted into thunderous cheers and applause as King appeared Saturday night, sitting at a baby grand piano and showing all the love in her heart as she sang “Beautiful,” the final song.

“It’s kind of miraculous that this show has lasted for five years because not many do. And it’s a testament to, I think, people say the music … but the book is so good and the direction and the lighting and the sets. It’s really a well put together production,” King said in an interview with The Associated Press after the show.

She has sung onstage during curtain calls during the show’s long run but has never appeared in the show itself.

In the show’s final scene — set during her famous 1971 Carnegie Hall concert — the 76-year-old King played a much younger version of herself as she took over for Chilina Kennedy, who recently returned to the Broadway production of “Beautiful” after playing the King role in the North American tour.

King and the cast then performed the show’s encore number, “I Feel the Earth Move,” at the curtain call as the audience danced and clapped along. The singer-songwriter held hands with Kennedy as the two took several bows and accepted flowers from the cast.

“Everyone connected with this show will agree that the people we have to thank the most are you, the audiences; please give yourselves a hand,” King told the audience, a sea of cellphones snapping pictures.

“It’s thanks to you, you who have come once … twice, three times,” she said. “I hear from people who’ve brought friends, family and shared the joy and shared the love, and it’s amazing.

“So if you keep doing that, you never know when I might show up again,” she joked.

Among the audience members was Chuck Schumer, the U.S. senator from New York, who waved to the crowd and gestured thumbs up as he exited the theater. “CBS This Morning” anchor Gayle King was also at the show and said it was her fourth time seeing it.

“I love it. I love her,” she said. “I still have my ‘Tapestry’ album.”

“Beautiful” is based on King’s life from when she was a teenage songwriter in New York, to her time as wife, mother and author of scores of recognizable songs. The show features a collection of famous pop music, written by King and her ex-husband Gerry Goffin, as well as Barry Mann and Cynthia Weil, including the classics “You’ve Got a Friend,” ”One Fine Day,” ”Up on the Roof,” ”You’ve Lost That Lovin’ Feeling” and “Natural Woman.”

King called seeing herself played as a character onstage “surreal” but said she is pleased the show has had such longevity.

“Beautiful” opened on Broadway on Jan. 13, 2014, and won the 2014 Tony Award for best actress in a musical for Jessie Mueller; the 2015 Grammy Award for best musical theater album; and two 2015 Olivier Awards, Britain’s version of the Tonys. Productions have played in London, Japan and Australia and toured the United Kingdom. The North American tour is celebrating its third anniversary of sold-out runs and is currently playing at Philadelphia’s Academy of Music.

When producers came to her to suggest she appear in the last scene to mark the show’s anniversary, King said, she did not hesitate.

“I totally envisioned that moment, and it was a thousand times more than I had imagined,” King told the AP.

“I love watching people come and see them forget about their cares and troubles for two hours and forty minutes,” she said. “It’s a wonderful feeling.”