The protagonist lives with his widowed father in Dublin and repairs vacuum cleaners in his electrical appliance store. On the side, he plays his scuffed guitar as a street musician and dreams of a career as a professional musician. A young Czech immigrant woman, who works as a flower seller on the street in Dublin and is later hired by a rich family as a cleaning lady, befriends him and soon encourages him to turn his dreams into reality.

Once is a 2006 Irish independent film directed by John Carney.
The film won an Academy Award in the Best Song category in 2008.