When Will Gluck signed on to direct Annie, he knew he wanted to update the music.
So he recruited songwriters Sia and Greg Kurstin to give the classic musical a modern-day feel.
“Sia is awesome,” Gluck tells PEOPLE. “I was super lucky that she was interested and she loved Annie as a kid.”
While the “Chandelier” singer was initially only supposed to write a song or two for the film, Gluck eventually convinced her to come onboard for the whole thing.