The Exorcist, directed by William Friedkin, can be classified as a New Hollywood film as it follows many of the characteristics of the movies of that time period and of the stylistic times. Among these would be the appearance of swearing heavily after not previously being shown in films of previous eras, rough cinematography style, heavy use of music to aid the scenery and images, and other characteristic defining as a film of this era. The film, based on a true account of exorcism adapted from a book written by William Blatty, features two Jesuit priests called to perform an exorcism on a girl believed to be possessed by Satan, who are ultimately killed in the process of performing the exorcism. The film makes heavy use of lighting and several special effects related as being very advanced for the period. The music also factors heavily into the overall production of the film using it to mark key moments and other important factors within the film.