After World War II, Hollywood produced a series of low budget pictures characterized by a dark mood, bleak urban landscapes and fierce violence. French critics called them <i>films noirs</i> (black films). These movies presented a critical vision of the social injustice present in the American capitalist society. This thesis examines the socio-political dimension of <i>film noir</i> firstly through its social, literary and filmic origins, then through a piecework study of shots and dialogues from six <i>noir</i> pictures: <u>Body and Soul</u> (1947), <u>Force of Evil</u> (1948), <u>Knock On Any Door</u> (1949), <u>Kiss of Death</u> (1947), <u>I Walk Alone</u>(1948) and <u>The Set-up</u> (1949). It is shown how the Marxist convictions of their makers influenced their style and their content. Even <i>films noirs</i> made by apolitical or moderate filmmakers follow a similar pattern. It is concluded that <i>film noir</i> contains expressions of anti-capitalist struggle toward social justice and moral redemption. The appeal of these ideas to many Americans is shown by the box-office success of these pictures, while many <i>noir</i> writers, actors and directors were the victims of the reactionary repression of the early fifties. / Master of Arts