Inside the ‘Frozen’ dress rehearsal: Broadway’s new musical prepares to lift the curtain

“Frozen” co-creator Jennifer Lee and her boyfriend, Alfred Molina, sit toward the front of the historic St. James Theatre late Tuesday afternoon for a special dress rehearsal of the new Broadway musical.

The production has invited industry people — mostly cast and crew of other Broadway shows, including Disney Theatricals’ “The Lion King” and “Aladdin” — to a sneak peek of the upcoming show just two days before the first public preview.

Lee, who wrote the book for “Frozen” in close collaboration with songwriters Robert Lopez and Kristen Anderson-Lopez, clutches a pen and a notebook. The team is still reworking the opening number, she says, so she’ll be taking notes.

“We ran out of time in rehearsal,” she says, smiling and confessing that she has more nerves than she thought she would for this show. That’s despite the fact that this type of industry rehearsal — known by the terribly politically incorrect term “gypsy run” — always has warm and responsive crowds. This packed, whooping and hollering house is no exception.

Lee is still on edge.

“We were having lunch and I was just staring at him,” she says of Molina.

The afternoon is uncharacteristically warm for a winter day in New York City, with temperatures outside in the 60s. The icy terrain of the elaborate set contrasts sharply with the breezy tops and light jackets of audience members who snaked down 44^th Street and into the theater not long ago.

“I need the audience again to know what I need to do, so this is great,” Lee says as director Michael Grandage takes to the stage to deliver a brief introduction that is met with an inordinate amount of applause.

“It is important that you’re here. This is our first opportunity to see and feel what a full house is like,” he says to the crowd, adding: “You at least know how we feel.”

As the lights dim, Molina wraps his arm around Lee’s shoulder and whispers in her ear. Toward the end of the first act, during actress Caissie Levy’s rousing rendition of the power ballad “Let It Go,” Molina pumps his fist in the air. During intermission he reveals that the fist pump was the result of “waiting for the changes. Willing them to work.”

He’s seen every iteration of the show, he says, adding, “It’s beautiful, fantastic. It just keeps getting better and better.”

Indeed, after an early run at the Buell Theatre in Denver last year, as much as 30% of the show has been altered, the songwriters and Lee said. And that process of revision, as evidenced by Lee’s notebook, is still very much alive and well.

Lee is proud of the cast, though.

“I’m just blown away by them,” she says. “The audience has lifted them up.”

Lopez is calm and matter-of-fact during intermission. As co-creator of “Avenue Q” and “Book of Mormon,” he’s familiar with the process. He’s been watching today’s show with a critical eye, and he says he needs to see it with a paying audience to really feel how it’s landing.

“You’re always on pins and needles. You watch it knowing what you want to fix,” he says. “It’s one of those things where you bide your time and wait your turn until you make the final tweaks.”

He and Anderson-Lopez are Oscar nominees in the best song category for their work on “Coco.” After this show, backpacks slung over their shoulders, they stop to talk to a few fans before being ushered backstage.

As the crowd files out, a lone voice — small and sweet, but powerful — can be heard echoing off the peach-colored tiles of the lower-level women’s restroom.

“The cold never bothered me anyway,” a child sings. “Let it go! Let it go!”

Look for more coverage of “Frozen” on Broadway this week at latimes.com/arts.

jessica.gelt@latimes.com

Twitter: @jessicagelt

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