 Singer asked him not to use any songs in the soundtrack as he "didn't want to date the movie".Due to Kamen's unfamiliarity with the comics, he only tried to "represent Bryan Singer's filmic tone that he's made, for a comic book, a quite serious movie, which is about the capacity of humanity to categorize people by race, religion or type, and prejudice people against them based on their innate characteristics".Character-specific themes were written to "identify these characters, as you go through the film, because they're not always clear."