The unnamed narrator is discussing with the famous Parisian amateur detective C. Auguste Dupin some of his most celebrated cases when they are joined by the Prefect of the Police, a man known as G-. The Prefect has a case he would like to discuss with Dupin. A letter has been stolen from the boudoir of an unnamed female by the unscrupulous Minister D-. It is said to contain compromising information. D- was in the room, saw the letter, and switched it for a letter of no importance. He has been blackmailing his victim. The Prefect makes two deductions with which Dupin does not disagree: The contents of the letter have not been revealed, as this would have led to certain circumstances that have not arisen. Therefore, Minister D- still has the letter in his possession. The ability to produce the letter at a moment's notice is almost as important as actual possession of the letter. Therefore, he must have the letter close at hand.