Opening on the streets of Dublin with a long range shot of a busker with young drunk urinating behind, Once immediately takes off when the drunk cleverly snatches up the donations with the red-haired musician in hot pursuit. The chase ends happily, as it only could in Dublin, and we are immediately signaled that this is a fresh story—a very real and honest one. Dubbed an "art house musical" by writer/director John Carney, Once works tremendously as a very natural and believable character study of two people attracted through music who then struggle to sort out their lives and relationships.

On the streets protagonist (Glen Hansard) plays what people want to hear during the day and rehearses his own angst-ridden songs at night while earning subsistence wages at his father's vacuum cleaner repair shop. The source of the romantic young busker's intense material is his recent breakup with a girlfriend now living in London, and it works especially well since Hansard is a professional songwriter-singer with the Irish band called the Frames. His heartfelt song touches a young Czech woman (musician and songwriter Markéta Irglová), and she soon after takes him to a friendly music store where she regularly practices piano.

They tentatively begin playing one of Hansard's creations, and the result is magical. He asks her to collaborate on a romantic tune since he doesn't feel he can adequately pen the lyrics. It turns out that she has her own relationship challenges, having left her husband behind in Czechoslovakia to live in Dublin with her mother and young daughter. A Hollywood treatment would have these two falling madly in love, abandoning all else to follow up their obvious passion for music with lustful abandon.

Fortunately, Once has much higher ambitions, as potent as a Wong Kar Wai treatise on unrequited love and as true to life as Richard Linklater's Before Sunrise/Before Sunset. A sweet slice of life that acknowledges the power of music, it reaches its climax inside a recording studio when the musicians pour out their souls so thoroughly that they awaken the sound engineer and create a sublime song. A very poignant moment serves as the final denouement as the camera tracks backwards from the Irglová's apartment window, assuring us that both lead characters have grown tremendously from their chance encounter. Anyone who has found a soul mate will acknowledge the gesture with a knowing smile. It's very honest and real.