In the early days of documentary filmmaking, entertainment industry documentaries often took the form of exposés or biographical portraits. Films like "The Day of the Locust" (1975) and "Inside the Mafia" (1980) offered a gritty, unflinching look at the darker side of the industry. These documentaries often relied on interviews with industry insiders, archival footage, and investigative reporting to uncover the truth behind the glamour of Hollywood. More recent documentaries, such as "The Imposter" (2012) and "The Act of Killing" (2012), have continued this tradition, using innovative filmmaking techniques to shed light on the complexities of the entertainment industry.