"The Murders in the Rue Morgue" is a short story from 1841 by Edgar Allan Poe. It features the brilliant deductions of Auguste Dupin and is one of the first detective stories. Though not the first of its kind, "The Murders in the Rue Morgue" is almost certainly the first locked room mystery. It first appeared in Graham's Magazine in April, 1841.

Plot

Auguste Dupin investigates a series of baffling deaths of Parisians, who are brutally killed in apparently inaccessible rooms. Dupin reaches the astounding conclusion that killings were not murder per se but were carried out by a wild "Ourang-Outang," the escaped pet of a sailor.

Quotation: Poe's rules for the locked room

From the story:

Let us now transport ourselves, in fancy, to this chamber. What shall we first seek here? The means of egress employed by the murderers. It is not too much to say that neither of us believe in praeternatural events. Madame and Mademoiselle L'Espanaye were not destroyed by spirits. The doers of the deed were material, and escaped materially. Then how? Fortunately, there is but one mode of reasoning upon the point, and that mode must lead us to a definite decision. --Let us examine, each by each, the possible means of egress. It is clear that the assassins were in the room where Mademoiselle L'Espanaye was found, or at least in the room adjoining, when the party ascended the stairs. It is then only from these two apartments that we have to seek issues. The police have laid bare the floors, the ceilings, and the masonry of the walls, in every direction. No secret issues could have escaped their vigilance. But, not trusting to their eyes, I examined with my own. There were, then, no secret issues. Both doors leading from the rooms into the passage were securely locked, with the keys inside. Let us turn to the chimneys. These, although of ordinary width for some eight or ten feet above the hearths, will not admit, throughout their extent, the body of a large cat. The impossibility of egress, by means already stated, being thus absolute, we are reduced to the windows. Through those of the front room no one could have escaped without notice from the crowd in the street. The murderers must have passed, then, through those of the back room. Now, brought to this conclusion in so unequivocal a manner as we are, it is not our part, as reasoners, to reject it on account of apparent impossibilities. It is only left for us to prove that these apparent 'impossibilities' are, in reality, not such.

External links

• Full text
• Origins of Detective Fiction