Edgar Allan Poe's short story, The Purloined Letter, is a detective story that has as it's main theme simplicity. When considering this story in terms of mystery and suspense, we must consider an underlying theme: those things that are sought are often simply left out in the open.
In the Purloined Letter, I believe that Edgar Allen Poe wrote the story to seem as though it is a mystery when in fact it is anything but a mystery. It cannot be a mystery because everything that constitutes a mystery, motives and execution, how to find and convict the culprit, are all told to the reader in the beginning of the story. The only problem presented to the reader is the finding of the letter and the deceit that was committed when the letter was stolen. This is not a simple fable written by Poe to teach a flimsy moral.
If there is any mystery at all it is the stupidity and incompetence of the character, the Prefect, in finding the letter. Poe wrote this story in such a manner.
The reason Lacan gives in his seminar for wanting to evaluate" The Purloined Letter" is that the drama, the narration and the conditions of that narration could be distinguished. Lacan felt these components were important. In" The Purloined Letter" the narration is particularly important because you need the commentary on the drama to make the story more interesting.
Poe uses a style of writing that is purposefully used to trick the reader into believing something other than what Poe intended. He uses his characters and fictive creations to delude the reader. He shows us this not only in the way the story is written but also in the relationship between the characters the Prefect and Dupin. In the...