Dupin and his companion create their own artificial environment, they are "enamored by the night for her own sake" (Poe, 65). They close the curtain during daytime and they only go out at night. They almost never leave the apartment and Dupin solves the crime by merely reconstructing second hand information. But the artificial environment does not stop here: it is mirrored, or repeated, in the scene of crime. In "The Murders in the Rue Morgue" we are confronted with the classical case of the 'locked-room mystery'. Cawelti has outlined the important functions of this setting:

First of all, it furnishes a limited and controlled backdrop against which the clues and suspects so central to the story can be silhouetted. It abstracts the story from the complexity and confusion of the larger social world and provides a rationale for avoiding the consideration of those more complex problems of social injustice and group conflict that form the basis of much contemporary realistic fiction (97).

it is sufficient to note that the central topic ... grows out of the allegory of the cave's valorizing of mind at the expense of the body, that is, out of Poe's sense of his detective Dupin as a kind of Platonic embodiment, a sedentary mastermind whose very lack of physical exertion emphasizes the mastery of mind over the material world (Irwin, Introduction xvi).

Normally the detective hero is introduced at the very beginning of the plot, in an episode that demonstrates the brilliance of his deductive mind and ensures the reader that he will be sure to solve the mystery, however intricate and complicated it may be. According to Dorothy Sayers it is this reassurance that "the ultimate mystery of life and death will be solved for us" (Cawelti, 98) that causes people to indulge into mystery stories in the first place. As often with popular fiction it has the function to distract and entertain an audience making sure that easy solutions will be in reach. "Poe's Dupin stories explored the terms in which the secret depths might be brought under control and the sense of hidden guilt and insecurity overcome" (104). This can only be achieved through the intellectual hero who takes the reader by the hand and leads him through the confusions of the plot, until he finally redeems society's guilt by naming the killer who can then be punished in the name of the people.

In the classical detective story, the detective takes the center of the action. All the other characters, or better types, are peripheral to his genius mind. This leads directly to the importance of the plot, if not to say its dominance over psychological development. Neither the detective's psyche, nor those of the other players seem to be essential. The detective's persona circles merely around the "unriddling of the riddle" (Poe, 80). The other persons, and the environment in which they appear, vanish once the mystery is solved. In other words, the narrative process itself becomes the driving force in the detective story.

Cawelti distinguishes six main phases within the detective story pattern:

(a) introduction of the detective; (b) crime and clues; (c) investigation; (d) announcement of the solution; (e) explanation of the solution; (f) denouement. (Cawelti, 82)⁸

[The] setting performs many functions ... it abstracts the story from the complexity and confusion of the larger social world and provides a rationale for avoiding the consideration of those more complex problems of social injustice and group conflict that form the basis of much contemporary realistic fiction ... The isolated setting has remained popular with classical detective story writers for another reason. It establishes a framework for the treatment of manners and local color ... these pageants of local color provide both an air of verisimilitude and an added source of interest to the main theme of investigation, in addition they symbolize the normally peaceful and serene order of society disrupted by the anomaly of crime and restored when the detective isolates the guilty individual. (97f.)