Composer Robert Lopez was surfing YouTube recently when he came across a video of a music box playing "Let It Go," a stirring, radio-friendly empowerment anthem that he and his wife, Kristen Anderson-Lopez, wrote for the upcoming Walt Disney Animation movie "Frozen."
This is the second Disney feature film for the couple, who also helped write the music for 2011's "Winnie the Pooh." But it's the first time their work has ended up in a pink box with twirling princesses — and in the lofty realm of Disney tunes that people can't seem to stop humming. Broadway performer Idina Menzel sings "Let it Go" in the movie, Disney Channel alumna Demi Lovato has released a pop version of the tune, and some amateurs have started to upload their own renditions to YouTube, including a 3-year-old who belts the line "Be the good girl you always have to be" with surprising feeling.
"When you're starting to craft a melody you're thinking to yourself — in the context of Disney — this could be an everlasting song," said Lopez, who has won Tony Awards for his work on the irreverent musicals "The Book of Mormon" and "Avenue Q." "Not every song you write in the course of your career has that chance."
"Frozen," which opens Nov. 27, is loosely based on the Hans Christian Andersen fairy tale "The Snow Queen." The story centers on two sisters, Elsa (voiced by Menzel), the soon-to-be queen tormented by her own mysterious powers, and Anna (Kristen Bell), Elsa's chipper and admiring younger sibling. Set among a fictional Nordic land of fiords and ice castles, the movie is sprawling in its visual scope and emotional range — factors that made it ripe, directors Chris Buck and Jennifer Lee have said, for a musical treatment.
"Music can get to the heart of an emotion so easily, and we wanted to keep driving the plot with it," Lee said. "What they could do with one song, it would take five or six scenes in a montage to communicate."
The Lopezes, who met at a songwriting workshop in 1998, live in Brooklyn with their two daughters, ages 8 and 4. Both were shaped by Disney movie music as children and saw "Frozen's" sisterhood story as resonant of the dynamic between their girls. Robert, 38, grew up in New York City, falling asleep at night to the record from "The Jungle Book"; Kristen, 41, loved "Mary Poppins" songs as a kid in the New York suburbs.
Eight of the couple's songs appear in the film, which also includes tracks scored by Christophe Beck. In "In the Summer," a naive snowman named Olaf (voiced by Josh Gad) pines for warm weather; in "Love Is an Open Door," Anna and a hunky prince named Hans (Santino Fontana) quickly find companionship.
In the story outline the directors and songwriters used to communicate with each other, there was a spot for something called "Elsa's Badass Song," a tune meant to communicate the character's inner strength and turmoil. In writing the song, which ultimately became "Let It Go," Anderson-Lopez said she and her husband listened to Aimee Mann and other singer-songwriters far from the traditional Disney oeuvre.
"I got very emo in the writing of this," Anderson-Lopez said. "We thought, 'This is an artist trying to find her own voice.' We tapped into, 'What is that experience where you stop caring what everybody thinks and start expressing what's really in you?' It's terrifying and exhilarating and a little bit selfish."