The unnamed narrator and his friend, C. Auguste Dupin, are interrupted by the intrusion of the prefect of the Parisian police, who bursts in to tell the tale of the theft of a compromising letter from the bedroom of the queen by the unscrupulous Minister D——. The contents of the letter are never made known, but the prefect avers that he has been charged with retrieving it, and he further reveals that so long as the letter remains in the minister’s possession, he will hold the queen in his power. The prefect details to the narrator and Dupin the extent of his searches of the minister’s apartments, and he confesses that even though he and his assistants have searched in every possible place, leaving no place unexamined, all of their efforts have been in vain. The letter remains concealed in a place undiscoverable by anyone.

Dupin questions the prefect closely about the methods and the places of his search, suggesting that it would appear that the letter is no longer in the minister’s apartments. He nevertheless advises the prefect to search them once more, inquiring as he does about the exact physical appearance of the letter, as well as its contents. The prefect departs in despair, and the story shifts immediately to his return to Dupin’s apartment a month later, at which time the letter remains, as far as the prefect can discern, in the possession of the minister. Dupin inquires as to the amount that the prefect would be willing to give to possess the letter, and when the latter names the sum of fifty thousand francs, Dupin offers to produce the letter for the sum named. He does so, much to the astonishment of both prefect and narrator (who is present at this second meeting as well), and after the departure of the prefect, tells the narrator how he came to recover the letter from the minister.

The secret of Dupin’s success, he asserts, lay in his capacity to read the intentions of the minister more accurately than the Parisian police. Briefly, Dupin realizes that rather than hiding the letter in some ingenious contraption or out-of-the-way place, the minister would realize that all such efforts would be fruitless in concealing the item from the searches that were bound to ensue on his having stolen it. Consequently, Dupin surmises that the minister would hide the letter in plain sight.

In a visit to the latter’s apartments, and under the cover of wearing dark glasses, Dupin surveys the sitting room and notices the letter dangling from a ribbon in the center of the mantelpiece, even though its outward appearance is such as to deny this possibility. Leaving a gold snuffbox in the minister’s quarters, Dupin thus provides himself with an occasion to return on the following day, at which time he arranges for a diversion that allows him deftly to substitute a facsimile of the letter for the authentic article and thus to possess himself of the letter and earn the reward. The tale ends with Dupin’s account of his previous relations with the minister, as well as the revelation of the message that Dupin had inscribed on the inside of the facsimile. The words are a citation from an eighteenth century play about the legend of the house of Atreus: “So funereal a design, if it is not worthy of Atreus, is worthy of Thyestes.”