Joker: Folie à Deux (Score from the Original Motion Picture Soundtrack) reteams composer Hildur Guðnadóttir with writer/director/producer Todd Phillips following their collaboration on the latter's 2019 blockbuster Joker, which earned more than $1 billion at the global box office and an Academy Award, Golden Globe, Grammy and BAFTA award for Guðnadóttir. For Phillips, the decision to bring her back to compose the music for Joker: Folie à Deux was an easy one. He had this to say: "There was no version of this film where we weren't calling Hildur to do the score. I think her music is basically the second biggest character in the first film."