Ernesto de Sousa, a pioneering figure in the Portuguese avant-garde movement, made significant strides in film and multimedia art during the 1960s and 1970s. His most notable work, *Dom Roberto* (1962), stands out as a crucial release that encapsulates his experimental approach to storytelling. This film, blending elements of theater and cinema, showcases his belief in art as an interactive experience, making it a sought-after title among collectors looking for unique cultural artifacts that challenge traditional narratives. Beyond *Dom Roberto*, de Sousa's involvement with the Fluxus movement and collaborations with artists like Robert Filliou and Wolf Vostell enriched his oeuvre, leading to innovative projects such as *Nós Não Estamos Algures* (1969) and *Almada, Um Nome de Guerra* (1969-1972). Collectors appreciate de Sousa's work not just for its artistic merit but also for its historical significance in connecting Portuguese art with international movements. His films remain a testament to a transformative period in cinema, embodying the spirit of experimentation that defined a generation.