The Purloined Letter

This story is about a letter which was used as a instrument of blackmail. It is interesting to note that the letter was only useful until the content of it were hidden and once they were revealed the letter would be of no use. The Prefect(Police Chief) was very meticulous in his search of the stolen letter but he lacks the creativity which would have allowed him to apply his professionalism in a manner more helpful.
The Prefect trained through his years of experience looked in every possible place where a letter can be hidden, what he failed to realise is that the letter is not hidden at all. A person not as blinded by his sense of "know it all" like Dupin applied his knowledge and figure out where that letter might be.
Dupin has hinted in the beginning of the story that the Prefect might not be very intelligent since he declared anything that he did not understand as oddity. Also when the Prefect laughed at the suggestion that it might be the simplicity of the thing that baffles him shows that he regard himself as highly intelligent.