The word «documentary», applied to the audiovisual fi eld, seems to be increasingly ambiguous.Nowadays, it is possible to fi nd many taxonomies and genres within what is called documentary fi lm as «documentaries» are produced.Nevertheless, something seems to remain clear: the documentary is in opposition to the so-called fi ction fi lms.At least, this is an a priori perception still operating among the spectators, warranting an image as «documentary»: it is assumed that the images are real in relation to the world that has created them.The main objective of this article is to propose an ethical/political perspective in order to think the division and juxtaposition of fi ction and documentary.Today, with the many transformations that have affected documentary cinema, the frontier that separates it from fi ction, is defi ned by this ethical/political thought related to the notion of ‹author› and the construction of the real thing inside an image.