The Murders in the Rue Morgue Poe's Dupin displays many traits which became literary conventions in subsequent fictional detectives, including Sherlock Holmes and Hercule Poirot. Many later characters, for example, follow Poe's model of the brilliant detective, his personal friend who serves as narrator, and the final revelation being presented before the reasoning that leads up to it. Dupin himself reappears in "The Mystery of Marie Rogêt" and "The Purloined Letter". The unnamed narrator of the story opens with a lengthy commentary on the nature and practice of analytical reasoning, then describes the circumstances under which he first met Dupin during an extended visit to Paris.
C. Auguste Dupin the three stories, Dupin travels through three distinct settings. In "The Murders in the Rue Morgue", he travels through city streets; in "The Mystery of Marie Rogêt", he is in the wide outdoors; in "The Purloined Letter", he is in an enclosed private space. Dupin is not actually a professional detective, and his motivations change through his appearances. In "The Murders in the Rue Morgue", he investigates the murders for his personal amusement, and to prove the innocence of a falsely accused man. He refuses a financial reward. However, in "The Purloined Letter", Dupin purposefully pursues a financial reward. While