Cinéma vérité (UK: , US: , French: [sinema veʁite]; "truthful cinema") is a style of documentary filmmaking developed by Edgar Morin and Jean Rouch, inspired by Dziga Vertov's theory about Kino-Pravda. It combines improvisation with use of the camera to unveil truth or highlight subjects hidden behind reality. It is sometimes called observational cinema, if understood as pure direct cinema: mainly without a narrator's voice-over. There are subtle, yet important, differences between terms expressing similar concepts. Direct cinema is largely concerned with the recording of events in which the subject and audience become unaware of the camera's presence: operating within what Bill Nichols, an American historian and theoretician of documentary film, calls the "observational mode", a fly on the wall. Many therefore see a paradox in drawing attention away from the presence of the camera and simultaneously interfering in the reality it registers when attempting to discover a cinematic truth.