Anton Karas asked a stunned Karas if he would compose the music for the film. Karas protested, saying he had never actually written music. As Karas later told the story, the director insisted and invited Karas to England. The Austrian became homesick and asked to be allowed to return. Reed told him he could—as soon as he had written the music. Under this pressure Karas wrote his Harry Lime theme. The film—with the music a contributing factor—was a gigantic success, and Karas' life was changed drastically. As a result, he toured all over the world and performed for many celebrities, among them
Birdman (film score) I needed something to help me find the internal rhythm of the film." He also wanted a score that "wouldn’t cater to an audience’s expectations", which the drums, being more abstract, provided. The official soundtrack was released on October 14, 2014. Iñárritu contacted friend and jazz drummer Antonio Sánchez in January 2013, inviting him to compose the score for the film. His reaction to writing a soundtrack using only drums was similar to Lubezki's thoughts of shooting the movie like a single shot: "It was a scary proposition because I had no point of reference of how to achieve this.