"When we were writing this we were very much writing about a character…and it wasn't until two days later that I was like, 'This is me.'" Billie Eilish and FINNEAS take us through a very intimate journey inside of their creative minds as they unveil how they created their soundtrack for the movie 'Barbie.' From the "physics" involved in the intricate production elements to Billie's "heartbroken" yet powerful delivery, the duo dissects every step behind bringing their hauntingly beautiful song to life.