Moran is a teacher of English and American literature. In this essay he examines the ways in which Sayers' story toys with the suspicions of the reader.

Suspicion is not less an enemy to virtue than to happiness; he that is already corrupt is naturally suspicious, and he that becomes suspicious will quickly become corrupt.—Joseph Addison

All reading is partially motivated by the suspicion of the reader. Anyone reading a work of fiction for the first time automatically raises his or her mental eyebrow when confronted with what seems to be an irregularity or odd occurrence in the fictional world that he or she has entered. In Hamlet, for example, the appearance of the Ghost puts the first-time reader in the same predicament as Horatio and the palace guards: Why has "this thing appeared again?" Does it "bode some strange eruption" to the state? Will...