"É o Boi" is a documentary that narrates the origins, portrays the present and discusses the perspectives of carnival in the city of Porto Ferreira/SP. Celebrating a tradition that already is already 90 years old, the film is mainly made up of images taken during the Porto Ferreira's carnival and interviews with people who fight daily to keep this unique and at the same time typically Brazilian cultural manifestation alive. Made over almost a decade, "É o Boi" also portrays critical moments of this carnival in the countryside of São Paulo, including disagreements with public authorities that almost led to the carnival being banned and the impacts of the Covid-19 pandemic on the organization of celebrations.