Any story must be dramatic in order to be interesting. The drama in a short story is almost always based on a single major conflict (although there might be minor conflicts that are incidental or part of the major one). A conflict in fiction—though not necessarily in real life—usually involves something tangible, or at least identifiable. This so-called “bone of contention” has come to be called the MacGuffin.
In Ibsen’s A Doll’s House the MacGuffin is a document forged by Nora which Krogstad threatens to use against her husband. In Tennessee Williams’s A Streetcar Named Desire, Blanche and Stanley are fighting over Stella, so Stella is the MacGuffin. Human beings are frequently used as MacGuffins. Countless stories have been written about abducted children, who are always the MacGuffins. The Indiana Jones movies always have very tangible MacGuffins, including a crystal skull and the Lost Ark of the Covenant. In Dashiell Hammett’s novel The Maltese Falcon, the MacGuffin is a fabulous statuette.
There is no interest without drama, no drama without conflict, no conflict without motivation, and no motivation without a MacGuffin. So the MacGuffin is the nucleus of the story.
In Poe’s story “The Purloined Letter,” the MacGuffin is obvious. The only problem, or conflict, is finding this letter. The story is a battle of wits between C. Auguste Dupin and the notorious Minister D-. Monsieur G-‘s account of the theft and the exhaustive efforts to recover the letter comprise the “back story.” The story proper begins when Dupin decides to recover it.
Dupin has at least three motives. Monsieur G- offers a reward of fifty-thousand francs (a sum that would have the purchasing power of at least $120,000 in current American dollars). Dupin also likes to use his analytical powers. And he tells his friend, “D-, at Vienna once, did me an evil turn, which I told him, quite good-humoredly, that I should remember.”
Dupin does not need to go over everything the police have done. He knows they were thorough. He tells the highly skeptical Prefect, “Perhaps it is the very simplicity of the thing which puts you at fault. . . . Perhaps the mystery is a little too plain.”
Dupin is right, of course. He visits the Minister and spots the purloined letter in a card-rack but disguised in outward appearance. He tells his friend, the narrator:
“But, then the RADICALNESS of these differences, which was excessive: the dirt; the soiled and torn condition of the paper, so inconsistent with the TRUE methodical habits of D-, and so suggestive of a design to delude the beholder into an idea of the worthlessness of the document,--these things, together with the hyperobtrusive situation of this document, full in the view of every visitor, and thus exactly in accordance with the conclusions to which I had previously arrived; these things, I say, were strongly corroborative of suspicion, in one who came with the intention to suspect.”
Poe’s story is all about the recovery of a missing document. There is no other significant conflict—although in the “back story” there are conflicts between the Prefect and the Minister and between the Minister and the “exalted” woman from whom he stole the letter. Although this information is rendered in the form of dialogue, it is no different in function from straight prose exposition.
Poe answers the question regarding the problem, or conflict, in the epigraph he attributes to Seneca:
Nil sapientiae odiosius acumine nimio.
An English translation would be:
Nothing is more hateful to wisdom than cleverness.
Nothing is more inimical to wisdom than cleverness.
The only problem in “The Purloined Letter” is finding the stolen letter. The police have used too much cleverness, and in doing so they have overlooked the obvious. C. Auguste Dupin tells Monsieur G-, the Prefect of the Parisian police, “Perhaps it is the very simplicity of the thing which puts you at fault.” And again, he says, “Perhaps the mystery is a little too plain. . . .A little too self-evident.”
Monsieur G- ridicules these suggestions and in the end says, “I would really give fifty thousand francs to any one who would aid me in the matter.” No doubt Monsieur G- would collect considerably more than fifty thousand francs if he could retrieve that letter.
There is no question who stole the letter. It was the Minister D-. There is no question that he has it in his possession. The only question is where he keeps it. The Prefect explains all the measures taken, including examining and probing every inch of the perpetrator’s apartment and waylaying him twice to search his person.
Once Dupin has determined that it is being hidden in plain sight, the problem is solved. Even if Dupin didn’t retrieve it personally, he could have revealed the secret to the Prefect and let the police recover it.
The main problem is one of blackmail; a letter containing very damaging personal information about the Royal family has been stolen, and the holder is demanding money - otherwise the contents thereof will be publicly disclosed. It is Auguste Dupin's challege to locate the whereabouts of the letter and "steal it back" in time:
The reason for the letter's theft is political in nature. The Minister, a political opponent of the Queen's, steals the letter, and holds it hostage. As the Prefect notes, "the power thus attained has, for some months, been wielded, for political purposes, to a very dangerous extent."
Dupin, who is an acquaintance of the Minister, is also a political ally of the Queen. As he tells the narrator, "You know my political prepossessions. In this matter, I act as a partisan of the lady concerned." This is one of the main reasons why Dupin is willing to get involved with the case and help find the letter.
The use of abstract logic and rationale to find the letter is very "Sherlockian," though written long before Sir Conan Doyle ever breathed life into the famous detective of Baker Street.
On a more internal level, the conflict of the story is one of sentiment versus reason. Under the duress of blackmail and extreme emotional stress, logic nevertheless prevails. In this respect, see the first enote reference below for further information.