Once

Once is a low-budget Irish movie about two musicians (Glen Hansard of The Frames and collaborator Markéta Irglová) who meet by chance and develop a relationship while writing and recording songs together. The film was made for €130,000 ($160,000 USD) and received significant critical acclaim for both its understated romance and for its music (no surprise, since Hansard and Irglová are professional musicians, not actors). The song "Falling Slowly" won the Academy Award for Best Song.

Almost missed its Oscar due to the fact that parts of the soundtrack, including the winning song, were released on other albums by the same artists prior to the film being released. It was decided to give them their nomination (and inevitable award) anyway since though it technically broke the rules, the film had been in the can over two years by the time it was released, and Oscar glory had been completely outside their expectations. But let it be understood on no uncertain terms, this was far and away the favorite song of the year.

At 19, Irglová is the youngest person ever to win the Best Song Oscar.

Before, during and after the release of the movie Hansard and Irglova have performed as The Swell Season and have released two albums under that name, 2006's The Swell Season (containing many of the songs in Once recorded during the long time it took to get the film made) and 2009's Strict Joy (featuring songs about the end of Hansard and Irglova's real romantic relationship). Both were extremely critically acclaimed upon release.

The film was adapted into a stage musical in early 2012, and holds the distinction of being the first musical ever to have a broadway run scheduled before it had even opened off-broadway. The show opened on March 18 to fantastic reviews, with most critics praising it for keeping to the spirit of the film while making the proper changes to make it work on-stage.

Tropes used in Once include:

Bilingual Bonus: That understated romance between Guy and Girl is never really resolved unless you know Czech. If you do, then you can understand what Guy couldn't when Girl answered "No, I love you."
Bittersweet Ending: Because the Guy Did Not Get the Girl.
Boy Meets Girl
Did Not Get the Girl: Contrary to what is expected of quirky romances, Girl remains faithful to her estranged husband (who returns by the end of the film), and Guy leaves on a jet plane to win back his ex-girlfriend.
Duet Bonding
Enforced Method Acting: The final scene when Girl tells Guy "I love you" in unsubtitled Czech was ad-libbed. Guy's look of confusion is genuine.
- The opening chase scene also qualifies; they shot without permits, so when the heroin addict runs off with Guy's money, a pedestrian wound up injuring the actor by trying to stop what he thought was an actual robbery.
Meet Cute

Guy: "Ten cents! That's brilliant! Thanks!"

The New Irish
No Name Given: Neither of the two main characters is ever referred to by name, and they're credited as "Guy" and "Girl." Guy's dad, Guy's girlfriend, Girl's husband and Girl's mother are also unnamed.
Race For Your Love: Guy searches for Girl before he leaves for his flight to say his goodbyes, but ultimately cannot find her. Instead, he sends her a piano, which is what she has always wanted.
Reality Subtext / Romance On the Set: Hansard and Irglová were indeed falling slowly.
- They didn't last as a couple. They broke up in 2008 while touring as The Swell Season, although they remain friends. Their 2009 album Strict Joy is about the end of their romantic relationship.
Shown Their Work: The film showcases Glen Hansard's knowledge of the minutiae of busking, such as cover versions earning far more than original songs.
Spiritual Sequel: in The Commitments, Glen Hansard plays Outspan and finishes the film busking on the streets of Dublin. Cut forward twenty years and Glen Hansard stars in film which opens with his character... busking on the streets of Dublin. Bonus points due the fact that his character in Once isn't named.
Throw It In: "Broken-Hearted Hoover-Fixer Sucker Guy" was just Glen Hansard goofing off between takes. Much to his surprise, it wound up in the final cut.
- Irglová's line, where she says "No, I love you," in Czech, was also an ad-lib, and Hansard's look of confusion is genuine.

The Broadway musical contains examples of

Adaptation Expansion: There are some new characters added and others have their roles expanded. For instance, the banker from the film who approves the loan due to his own love of music plays cello for the group's band.
Manic Pixie Dream Girl: Girl, probably due to the fact that it would be tough to make the painfully shy characterization from the film work well on stage.
Translation Convention: When two Czech characters talk privately, they speak English while Czech subtitles are projected above the stage. This later becomes a Checkovs Gun during the Bilingual Bonus scene mentioned above, where when she says I love you to Guy in Czech, it is subtitled in English.