In the film noir classic "Nightmare Alley" (1947), based on the novel by William Lindsay Gresham, Tyrone Power plays a sideshow barker in a seedy carnival which includes a geek biting the heads off live chickens. Power's character later succeeds as a charlatan mentalist, but then descends into alcoholism and is reduced to falsely portraying a geek as a means of survival in another sideshow. In one of Gresham's non-fiction books, Monster Midway, he details the process of making an alcoholic or a drug addict perform a geek act in exchange for a fix.