The Broadway version of the Dublin-based tale about an Irish busker and Czech immigrant who share their passion for music and a blossoming yet impossible love with a soaring soundtrack captured by the Oscar-winning song, "Falling Slowly," has hit the Great White Way to teary, standing ovations and rave reviews.

Critics on Monday called the intimate musical a "gem of a show", "a knockout,", "gorgeously crafted" and "the sweetest and most romantic show on Broadway" with talk already buzzing about a world musical tour and likely Tony Award nominations.

"'Once' uses song and dance in a way I've never experienced in an American musical," said The New York Times, complementing its soulful songs about the power of music and connection and performances by the musical's charming main stars, Steve Kazee and Cristin Milioti, as well as the supporting cast.

Before the musical's premiere on Sunday night, the success of the gentle film that starred songwriters Glen Hansard and Marketa Irglova playing a version of themselves, seemed difficult to top. Shot in 3 weeks on a shoestring budget, it ended up raking in $20 million worldwide.

The 2006 film, written and directed by John Carney, went all the way to the Oscars where Hansard told the awards show TV audience of nearly 40 million viewers: "We never thought we'd ever come into a room like this and be in front of you people."

The stage musical, adapted from a short off-Broadway run, was handed over to a different team of collaborators, including British director John Tiffany and choreographer Steven Hoggett, who created the acclaimed Scottish theater piece, "Black Watch."

Much of the film's humble story and witty tone has been kept in the musical. "There's a kind of humility to the film that we have tried to keep hold of, and a purity," Tiffany told Reuters.

The production uses more than a dozen actor-musicians, who stay on stage the entire show. Even before the musical begins, they play folksy music to audience members who can grab a drink on a makeshift bar on the stage, helping create the atmosphere of a Dublin pub setting.

"There is a simplicity about the fact that this is about the healing power of music. This is about seeing people create music and the effect and resonance that has on each other - and that is what the audience really seem to be getting off on," Tiffany said.

He also admitted, "I was obsessed with the idea of the audience being able to buy a drink."

IRISH FAIRYTALE

The musical's main differences include the Irish busker beginning his journey a more broken man, and the quirky Czech Milioti plays a larger, almost angel-like role inspired by the 1946 film, "It's A Wonderful Life."

"There is an element of fairytale to this story," Tiffany said. "She appears out of nowhere, just at the right time, and seems to have the energy and the resources to go with him on this journey for him to gain life back and to move on."

Several new songs were added by Irglova and Hansard, who have kept a low profile with the musical after spending years promoting and touring the film and becoming a real life couple before splitting up.

Reviewers gushed the show was as a textbook example of how to adapt screen to stage with a compelling story by Irish playwright Enda Walsh, heartfelt performances, subliminal choreography, a stylized set and unusual sound quality without relying on typical tricks of an outlandish Broadway spectacle.

But the musical also relies heavily on the same stirring songs and lyrics as the movie, said Tiffany, which he called "extraordinary."

"They story tell through it," he said, "that even though we don't necessarily have happy endings all the time in life, we can resource each other. The time we spend with each other can be enriching to the point that we can move on with the next part of our lives. That is a really sad and happy thing."

Already dubbed a Tony winner for best musical by some critics, Tiffany joked, "we don't talk about that", but he said, "I am so proud I have made the piece of work I wanted to make because you can't always say that."

As to its success so far, he wondered if it might simply be a sign of more humble times in society with audiences yearning for something other than the splashy Broadway experience.

"Part of me wonders if it is a real sign of the times, to do with, not austerity, that's not the right word, but just to do with simplicity. Do we want something a bit different?"

(Editing by Bob Tourtellotte)

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