In Edgar Allan Poe's short story The Cask of Amontillado, Fortunato's captivity by Montresor in the middle of a carnival with no explanation amazes readers and leaves many unanswered questions in readers' minds, thereby leading to reductionist interpretations of the story. Each of these readings leaves some elements in the story in ambiguity, failing to integrate them into a totalizing interpretation of the story. The reading of the story in relation to the Freudian concept of the uncanny, however, helps us to understand the motive behind the murder, by revealing the unconscious mechanisms at work. In light of this, this study argues that as a murder story involving the cruel death of a helpless victim on the surface level, The Cask of Amontillado is based on what is left unsaid in the narrative. It arouses the sense of the uncanny, as what Montresor says on the conscious level in the guise of the heimlich turns out to be, on the unconscious level, actually a phantasy of acting out the repressed wishes that he had pushed back to the darkest recesses of his psyche because of their disturbing threat to his egotistical unity.