Singer/actor Glen Hansard shocked the audience at Once The Musical in Los Angeles on Friday (08Aug14) by leading the cast in a surprise singalong during the curtain call.

Hansard, who wrote the music and lyrics for the Tony award-winning musical as well as the 2006 romantic drama of the same name, is in the city for his gig at the Hollywood Bowl on Sunday (10Aug14), and he stopped by the Pantages Theatre to surprise patrons at the end of the show.

Following the curtain call, the show's star Dani de Waal announced a "special treat" for the audience and introduced Hansard onto the stage.

The Irish songwriter was welcomed with a standing ovation, and he told the crowd he had been trying to see the U.S. National Tour for the past 10 months but their paths kept crossing as he has been on a world tour.

He then led the cast in singing traditional Irish folk song The Auld Triangle by Brendan Behan, before inviting the audience to join in a singalong.