A documentary tracing the case of a factory closing, through the experience of the workers, can provide an anthropologist with a useful material, provided the documentary analysis is set in light of the attention attached to the cinematographic composition and its techniques (editing, centring, camerawork) so as not to make an interpretation. This is being discussed in the paper devoted to the study of the movie “Rêve d’usine” (“Factory Dream”) in which the director Luc Decaster reveals the particular aspects of a struggle in the factory.