Idina Menzel and Josh Gad Have ‘Frozen’ Reunion at Broadway’s ‘Gutenberg! The Musical’ (Exclusive Photos)

Broadway audiences on Sunday were treated to one magical reunion when Idina Menzel joined her Frozen costar Josh Gad on stage at Gutenberg! The Musical.

The actress — a theater veteran and Tony winner for her role in Wicked — appeared at the end of the comedy in the "Producer" role, surprising the crowd at the James Earl Jones Theatre in New York City.

The "Producer" role has been filled with one celebrity cameo after another since Gutenberg! began performances back in September. Stars including Nathan Lane, Ben Platt, Cynthia Erivo, JJ Abrams, Marcia Gay Harden, F Murray Abraham, Lin-Manuel Miranda, Amber Ruffin, John Stamos, Patti LuPone, Debbie Gibson, Tiffany Haddish, Victor Garber, Sara Bareilles, Steve Guttenberg, Billy Crystal, Steve Martin and Martin Short (among many, many others) have come through so far.

Earlier this month, Kristen Bell — another of Gad's Frozen costars, as the voice of Anna — stopped by, and posed backstage afterwards for pics with her husband Dax Shepard. Jonathan Groff, who voiced Kristoff in the Disney animated films, has also guested.

The show stars Gad and Andrew Rannells — reunited onstage after their breakout roles in The Book of Mormon — as Bud and Doug, two aspiring musical theater composers who rent out a theater for a reading of their bio-musical of Johannes Gutenberg, the inventor of the printing press. The "Producer" part appears at the end of the musical, to offer the pair a contract.

Menzel, who stars as Elsa in Frozen alongside Gad's Olaf, was sure to make mention of her animated success when she took the stage Saturday.

"I'm a famous Broadway producer, and a Tony winner and a Disney queen," she said, before joking about John Travolta's legendary mispronunciation of her name: "And so on behalf of everyone at Adele Dazeem Productions, I hold in my hands a Broadway contract!"

"Congratulations Bud and Doug, I love you! You've got your show!"

She also sang a few notes from her iconic Wicked rallying cry, much to Gad and Rannells' joy.

Just last week, Walt Disney Company CEO Bob Iger revealed that there will be a fourth installment of the popular animated musical franchise, nine months after announcing an upcoming third Frozenmovie. "Jenn Lee, who created the original Frozen and Frozen 2, is hard at work with her team at Disney Animation on not one but actually two stories," Iger said.

Gad offered some insight into the films during an appearance on The View Monday. "I’ve heard a little bit and I can tell you guys, it’s pretty mind-blowing what’s coming," he said. "It’s pretty exciting."

He went on to note that reuniting with Menzel, Bell and Groff at Gutenberg! has allowed him a chance to stay up-to-date on what's happening with the sequels. "It’s been so great because Kristin, Idina and Jonathan have all come to be guest producers. So we’ll come backstage and we’ll all talk Frozen and then talk this other thing," he said.

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Gutenberg officially opened on Oct. 12. The original musical features a score and book by Scott Brown and Anthony King.

The limited production is currently slated to close on Jan. 28, 2024. Tickets are on sale now.