‘Once,’ an Irish-Czech love story, makes its Broadway debut (VIDEO)

"Once," 2006's charming indie Irish film that was adapted as a play, made its Broadway debut on Sunday to critical acclaim, the New York Times reported. 

The film, which won a 2007 Academy Award for its hit song “Falling Slowly,” first premiered on stage at The New York Theater Workshop in November last year, and is now at Broadway's Bernard B. Jacobs Theater. 

"When I first saw the musical 'Once' at the New York Theater Workshop last December, it registered as a little too twee, too conventionally sentimental, for the East Village," Times theater critic Ben Brantley wrote. "Yet on Broadway […] what is essentially the same production feels as vital and surprising as the early spring that has crept up on Manhattan." 

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The musical follows the love story between Guy, Irish street musician who repairs vacuum cleaners, and Girl, a Czech flower seller, who meet in Dublin, the Associated Press reported. Guy is mourning a lost love, and Girl is a lonely single mother, but the two connect over their passion for music.  

The low-budget film was based on the lead actor and musician Glen Hansard, who wrote the film's songs with his co-star Marketa Irglova. The movie was made for about $150,000, and grossed $20 million, according to the AP, and many credit its' success with the beauty of the soundtrack. 

The Broadway adaptation stars Steve Kazee and Cristin Milioti, and is directed by John Tiffany. It was adapted by Dublin-based playwright Enda Walsh and choreographed by Steven Hoggett. 

“[Hansard and Irglova] have written such gorgeous music,” Milioti told Broadway.com, “And they've gotten a group of people together who just absolutely love playing it and that's intoxicating. That was definitely what made me fall in love with it.”

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The intimate portrayal of the complexities of romantic relationships has transferred well to Broadway, where it is performed by just a 12-person cast, according to the critics. 

"In its new incarnation this musical reveals itself to be a show that was always meant (and probably lusting) for a brighter limelight and a bigger stage," wrote Brantley. "You have to watch out for those shy ones." 

"The new musical […] is the likely winner of the Tony Award for Best Musical," Forbes' entertainment writer Roger Friedman wrote. "The show is a knockout, even better now that it’s transferred uptown."