Greta Gerwig and the creative team of the film 'Barbie' discuss the musical evolution of the movie and how the pop songs influenced the score, tone, and even Barbie's heart. They talk about collaborating with artists like Dua Lipa, Nicki Minaj, Lizzo, and Billie Eilish, blending pop songs with the score, and creating a song with Dua Lipa. The speakers also explore the impact of specific songs on the connection between Barbie land and the real world, and the process of creating the soundtrack.