This is one of Poe's great mysteries for me because it uses logical deduction to find a treasure. The narrator is recalling a story of his friend Dr. Legrand. They met by accident, but became friends and visited together often. Legrand finds a "gold bug" and draws a picture of it on some parchment. Further along in the story the Narrator and Legrand find Captain Kidd's hidden treasure. It is then that Legrand describes in detail the exact sequence of logical thought patterns which led him to the discover. The complete summary and critical analysis can be found at E-Notes under "The Golden Bug."