NEW YORK — The puzzles the Tony Award-winning British director Michael Grandage has to sort out in his latest project are not the kind they train you for in a high-toned London drama school.

For example: dealing with a character with a carrot nose who’s prone to melting.

But when the project is “Frozen,” a stage version of the 2013 animated Disney film that made $1.3 billion at the worldwide box office, you sure as heck better have beloved figures such as Olaf the Snowman down, er, cold. So, in a ritual developed over the 17 months that Grandage and his team have been working on the musical — whose cost he hasn’t even wanted the entertainment company to tell him — much back-to-the-drawing-board discussion revolved around giving flesh to the movie’s whimsical creatures. As well as a thousand other design and dramaturgical elements to satisfy the legions of fans who Disney hopes will storm the ramparts of Broadway’s St. James Theatre, where performances began Thursday.

Olaf the Snowman, Sven the Reindeer, all those mystical trolls who live deep in the Scandinavian woods of Elsa and Anna’s meteorologically challenged kingdom of Arendelle: It was the task of Grandage — a man wholly new to the Disney empire and who had never directed an original musical — to take the ingredients of a mega-triumph and, well, merely whip up another one.

No pressure! 

Grandage recalls the importance that executives such as Thomas Schumacher, Disney Theatrical Productions president and producer, placed on getting “Frozen” right: “ ‘It’s a big property for us,’ they said, ‘And we’d like it to not depart too much from what’s out there. But it’s over to you, how to reimagine it.’”

Which brings us back to Olaf, voiced in the movie by “The Book of Mormon” veteran Josh Gad and depicted by Disney’s animators as three independently mobile balls of heartwarmingly mischievous snow. “That’s your first question when you do a stage version,” Grandage says, taking a break from rehearsals to talk on a recent weekend morning. “Do you do Olaf as a man in a costume like in Times Square?” he asks, laughing. “Or do you do a puppet?”

The answer, as often evolves in the best of Disney’s stage adaptations of its animated movie musicals, is a hybrid product of adult perspiration and child-friendly inspiration. The fusion of man (actor Greg Hildreth) and puppet arrived at, Grandage says, “invites you, the audience, to see Olaf through a person, because you’ve got the face of a real actor doing proper acting, and this puppet that sits in front of him. So you’ve a duality of both an iconic picture of an Olaf, with a human face operating and living through him.” 

Disney likes to hire directors who don’t just reorchestrate, but also can cogitate freshly about what on the surface might merely seem easily digested fairy tales rendered immaculately on celluloid. This has not always translated into success on Broadway: Think of opera director Francesca Zambello’s overproduced “The Little Mermaid” or design auteur Bob Crowley’s turgid “Tarzan.” When it does work, though, as in Julie Taymor’s visually ravishing “The Lion King,” the enchanting results fulfill the artistic mission the company has striven to uphold as it continues the tradition of big-time transferences from screen to stage it commenced with “Beauty and the Beast” in 1994.

For Grandage, the challenge has not only been to accept the magnitude of expectation fans of the movie would bring into the theater — “You realized you were taking on something that has seeped so deeply into the consciousness of people globally” — but also to bring to the fore an emotionality better suited to characters in three dimensions.

 “It’s a show that’s very much about a family in trauma,” says Kristen Anderson-Lopez, who with her husband, Robert Lopez, wrote the score for the film and added more than a dozen other songs for the Broadway version, which of course retains the Oscar-winning “Let It Go.” That was sung on screen by Idina Menzel as the tormented Elsa, the young queen cursed with an ice-making power that bedevils her subjects and sends her into self-imposed exile. 

And it’s a show in which frostiness itself is almost a character. As the director notes of the Disney designers he has worked with, alongside his life partner and “Frozen” set and costume designer, Christopher Oram: “There was a guy who showed us 100 different kinds of snow!”

The 55-year-old Grandage, who won the Tony in 2010 for his direction of “Red,” John Logan’s portrait of abstract-expressionist painter Mark Rothko, might seem at first blush an unconventional choice to tell the story of the clash between a pair of royal sisters, here played by Caissie Levy (as the brooding Elsa) and Patti Murin (as the sunnier Anna). Virtually all of his Broadway work has been with language-rich plays: “Frost/Nixon” with Frank Langella and Michael Sheen; “The Cripple of Inishmaan” with Daniel Radcliffe; “Hamlet” with Jude Law; his one previous musical on Broadway was a revival of “Evita.” But the résumé of this onetime actor, a graduate of London’s Central School of Speech and Drama, also includes high-visibility leadership positions, such as his stewardship of London’s esteemed Donmar Warehouse.

Grandage also is a bit of an entertainment conglomerate himself, heading up his London-based outfit — the Michael Grandage Company. He has carved out a director-producer role, a kind that few of his American peers develop, and his appetite is voracious: Right after “Frozen,” Grandage returns to London to direct his company’s revival in the West End of “Red” with original star Alfred Molina, along with Alfred Enoch, and then another Michael Grandage Company production, of playwright Martin McDonagh’s super-bloody terrorism satire, “The Lieutenant of Inishmore,” with “Poldark’s” Aidan Turner.

“I was terrified,” says Nicole Kidman, whom Grandage guided to a major London acting prize — the Evening Standard Award — for her performance as an overlooked DNA researcher in Anna Ziegler’s “Photograph 51.” (The play had begun life in a small theater in Maryland.)

 “And he just kind of simplified the whole thing, took me back to my basics,” Kidman says of the director in a phone interview. “He’s deeply intellectual and a stickler — you knowing all your lines — and it’s just about the work and I love that. It’s no frills, and I love that commitment.”

The stage is by far where Grandage has had his sharpest impact; a 2016 film he directed, “Genius,” starring Law as author Thomas Wolfe and Colin Firth as revered American book editor Maxwell Perkins, garnered disappointing notices. It’s too soon to tell, either, where “Frozen” will land on the spectrum of Disney’s artistic ventures. In a review of the tryout run of the show in Denver in September, Jesse Green of the New York Times wrote admiringly about some aspects but came away decidedly mixed about the story, by Jennifer Lee. “ ‘Frozen,’ ” he observed, “is going to have to figure out how to make the dark character less of a bore and the light character more compelling.”

Grandage had never been involved in a “trial” run before yet says he found the response “very helpful, actually.”

“I said to Tom Schumacher, ‘Do you know what? You add up the body of opinion that’s come from our own collaborators, us in the room, the audience in Denver and the critics, and you throw it all together. What emerges is a real road map here. We’ve got five months to do something where we can change.’ And if that’s not the point of having an out-of-town trial, what the heck?”

Broadway audiences will see a show that’s about 30 percent different from what was seen in Denver, Grandage and the Lopezes say. “A character we created we got rid of, we changed the opening, we changed the closing, we changed four huge numbers of choreography. And the whole reason is to make it more poetic, clearer, more precise,” Grandage explains.

“We totally rewrote the finale,” says Kristen Anderson-Lopez. Everyone agreed that “Frozen’s” teary wallop of a conclusion — a surprise final twist in the plot — had to land like a haymaker. It’s a statement about looking past pain, to an understanding of what’s most important in life, and remaining open to the possibilities of reconciliation in ways that you’re not always prepared for.

Grandage says he thinks they’ve found the sweet spot in the tale. He suspects it was the philosophy he has put into practice in other productions — to drill back down to the emotional basics — that won him this job in the first place.

 “Quite often I’ve said to [Schumacher] and others, ‘I would like to do this in the simplest form first,’ and quite often, we’ve all gone, ‘You don’t need a few hundred thousand dollars’ worth of fireworks here.’ ”

He says he trusts simplicity and hopes that’s apparent in “Frozen.” In some of his best work, Grandage adds, “I have no effects whatsoever, except the imagination of the audiences, and the brilliance of the actors, and the light.”

Frozen, book by Jennifer Lee; music and lyrics by Robert Lopez and Kristen Anderson-Lopez. Directed by Michael Grandage. At the St. James Theatre, 246 W. 44th St., New York. Call 866-870-2717 or visit