In this story, too, we also see so many of the features that Conan Doyle would go on to use to such effect in his Sherlock Holmes stories. In summary, it’s perhaps possible to become too obsessed with understanding something, with the result that one misses the obvious – in this case, the fact that the letter has been placed in just about the most visible and easily discovered place imaginable … with the result that it isn’t discovered (at least not by the police prefect). Eliot once complained that an early reviewer of The Waste Landhad ‘over-understood’ the poem. It seems to invite interpretation as a parable about the dangers of over-interpretation. The epigraph, which Poe attributes to the Roman writer and philosopher Seneca, translates as: ‘Nothing is as hostile to wisdom as too much subtlety.’ The idea of the purloined letter ‘hiding in plain sight’ makes the story archetypal in its ability to carry symbolic significance. This is probably why so many twentieth-century thinkers, from the psychoanalyst Jacques Lacan to the founder of deconstruction, Jacques Derrida, were so interested in it. ‘The Purloined Letter’ has the force of a fairy tale or parable: there is a purity to its plot, a simplicity, an ability to resonate with deeper philosophical meaning.

(Dupin also reveals that he owes the minister some payback after ‘an evil turn’ the minister did to him in Vienna.) The reference is Dupin’s way of saying he has discovered the minister’s plan, and foiled his scheme. In the substitute letter, Dupin reveals that he left a sheet on which he had written words taken from Prosper Jolyot de Crébillon’s Atrée: ‘A design so deadly, if not worthy of Atreus, is worthy of Thyestes.’ The lines allude to the story from mythology, in which King Atreus of Mycenae, in revenge for his brother Thyestes’ seduction of his wife, kills Thyestes’ sons and serves them to him in a pie.

Poe the purloined letter