The protagonists of the film are musicians and they actually played their instruments while shooting the scenes with music. Director Gustavo Galvão put together the fictional band Animal Interior ("inner beast", in English) especially for the project, with trumpeter and singer Ayla Gresta, guitarist Gustavo Halfeld, drummer Hélio Miranda, and bass player Vanessa Gusmão. The band rehearsed for three months before shooting started.
The book Karen leafs through when she visits Martin in a bookstore in Berlin is "Berlin Wonderland: Wild Years Revisited 1990-1996", edited by Anke Fesel and Chris Keller. The photographs shown in this scene were taken by Ben de Biel and Philipp von Recklinghausen.
Director Gustavo Galvão met bass player Vanessa Gusmão by chance in São Paulo, while she was working as sound re-recording assistant in Cristiane Oliveira's "Mulher do Pai" - of which Galvão is associate producer. He was already looking for musicians from Brasilia for this project when he found out that Gusmão was a bass player... And she's from Brasilia.