Willys de Castro was a painter, printmaker, draughtsman, and graphic artist, best known for his explorations of geometric abstraction. De Castro was an influential and active figure in the Grupo Neoconcreto, or the Neoconcretist Group, in Brazil. He began first to explore abstract geometric forms in painting and drawing during a graphic arts apprenticeship in 1950. Between 1959 and 1962, de Castro created his iconic “Objetos Ativos” series, which explored the plastic possibilities of two-dimensional planes and volume and questioned the pictorial role of canvas. As a result, his works were never strictly painting, but had qualities of sculpture. In his lifetime, de Castro also designed a number of costumes and sets.