As Douglas Winter writes, "In retrospect, the novel is noteworthy for what it is not: . . . its literary precedents are those of detective fiction rather than those of horror." Certainly, there are Gothic conventions in The Exorcist, including the monstrous body of Regan once she is possessed, the ancient and hidden nature of the menace, and the battle within an isolated place (refreshingly, a child's bedroom in Washington, DC, instead of a crumbling castle). However, for most of the novel, there are two mysteries: the question of what is happening to Regan, and the criminal investigation of the death of Burke Dennings.

With a detective story to take much of the readers' attention, supernatural elements are introduced slowly and carefully.

Noel Carroll offers The Exorcist as an example of the "complex discovery plot," in which, with the characters, the reader undergoes a process of "onset" (of inexplicable happenings), "discovery...