When Jon gets an
impromptu opportunity to tag a long with an eccentric budding
band called Soronprfbs — yeah, good luck with that one — he decides to take a chance and give it a go so hops in a van with a borderline mute drummer (Carla Azar), a French speaking guitarist (François Civil), a hotheaded theremin player (Maggie Gyllenhaal) and the
band's main man, Frank (Michael Fassbender), a lead singer who dons a giant fake
head on stage, off stage, in the shower and quite literally everywhere else.