Rainbow is a 12-year-old exuberant vlogger who embarks on a journey to Hell City, a tourist resort owned by the Devil’s son, in search of her long-lost father. The voyage takes place in an old ice-cream truck driven by the girl’s brother, Alek. Contrasting with his adventurous sister, Alek is a melancholic spirit who finds solace in making music.
During their journey, the siblings discover that their father, Klaus, traded his soul to the Devil to become a successful musician and a father capable of supporting a family (though it didn’t turn out as planned). Returning home won’t be easy, especially when Hell City proves to be alluring and Rainbow befriends the Devil, while Alek confronts his father.