The unwanted son of a prostitute, Bruno S. was beaten so severely by his mother at age 3 that he became temporarily deaf. This led to his placement in a mental institution; he spent the next 23 years in various institutions, often running afoul of the law. Despite this past, he a self-taught painter and musician; while these were his favorite occupations, he was also forced to take jobs in factories such as driving a fork lift. Director Werner Herzog saw him in the documentary Bruno der Schwarze - Es blies ein Jäger wohl in sein Horn (1970) and vowed to work with him, which led to his major roles in L'énigme de Kaspar Hauser (1974) and La ballade de Bruno (1977). He was very difficult to work with, though, sometimes needing several hours of screaming before he could do a scene.
