Arcade Fire are one of the most prominent bands of the 2000s. Having released four critically acclaimed albums, being one of the first "indie" bands to ever win Album of the Year at the Grammys, and being able to easily sell out almost all of their concerts, they have built up quite the reputation. Many people describe their sound as "orchestraic", which has resulted in their music being used in many movies and TV shows, and it comes as no surprise to many that the band have been asked to compose the music for many films.
One of these films was the 2009 film adaptation of Where the Wild Things Are. Spike Jonze, the film's director, asked Win Butler to help compose some of the music for the film. Exactly how much music was composed has been refuted many times, much to the point where it remains unclear. All that is known to exist is an acoustic re-recording of the song "Wake Up" from their 2004 debut, Funeral. This version was featured in the trailers, leading many people to believe that Arcade Fire was going to write music for the entire film. As a matter of fact, test screenings did happen to use the band's music in places as the film's actual music compositions had not yet been completed. The final product, though, ended up using music composed by Karen O from the Yeah Yeah Yeahs, backed up by other indie celebrities (such as Bradford Cox from Deerhunter).
It is unclear exactly how much, if any, Arcade Fire songs for the film still exist. Aside from the re-recording of "Wake Up", nothing has surfaced, though it should be kept in mind that Butler has neither confirmed or denied the existence of more material. While the music that ended up in the film fits perfectly and is still well-loved, many wonder how an Arcade Fire-composed score would have sounded.