This article presents a selection of observations from studies on the use of masks in expressions of popular culture, particularly those characterised by their collective nature, use of public space, and in-person participation. The study focuses on the role this artefact has played over the past decades in various communities across the city of Rio de Janeiro, Brazil. This focus is motivated by the role of the mask, in particular, as well as costumes more broadly, throughout the city’s cultural history, with Carnival being the event with the largest inflow of foreign currency and with the greatest cultural impact. In 2025 the capital had a hotel occupancy rate of 98.5%; in total more than 8 million people visited the city, generating an economic impact of approximately R$5.5 billion. However, the mask – a symbol of this event – has been undergoing a process of resignification in the community, revealing cultural “mismatches” in the relationship between the artifact and the territory.