Bates composed the score for "Guardians of the Galaxy" in 2014. Having worked with James Gunn in the past, Bates had a good idea on how Gunn wanted things done. Before any of the cinematography actually started, Gunn had Bates write several themes prior to shooting so the scene could be matched to the music instead of the score being created to fit the scene. This required a fair bit of cooperation between Bates and Gunn in advance since these scores would not only be the final piece, instead of a temporary filler acting as a placeholder, but they also influenced the actual performance of everyone on set. This amount of work and effort required a massive undertaking by both Bates and his team. For 4 months, they clocked upwards of 100-hour work weeks to produce this finished product. After all the work, they had a total of 29 different soundtracks giving a combined total of 64:34 of music. "At least half the cues in the movie have more than 500 tracks of audio," Bates was quoted in an interview with Melinda Newman on "HitFix". This was a result of there being orchestral passages that were doubled or tripled, choirs, overdubs, and other instrumentals.