As a trained mechanic, Jean Baier (1932–1999) developed an artistic fascination for practical shapes and the aesthetics of industrial manufacturing. With the spray gun he applied cellulose paint to sheet metal and aluminium. Strict clarity, angular lines and minimal chromaticity characterise his three-dimensional works. The film traces the artist’s impact on the discourse of Concrete Art from the 1960s to the 1980s with his numerous monumental wall designs for schools, car tunnels, swimming pools and hospitals.