It is one thing to take a beloved stage musical and successfully adapt it for the silver screen—and it’s a feat that’s given us everything from West Side Story to Chicago to Hedwig and the Angry Inch. But it is another still to build both the story and the music from the ground up, as writer-director John Carney has done since his 2007 musical hit Once, which tells the folk-infused tale of two buskers in Dublin.