Many characters in the novel have inner traits that contrast with their outward appearance, drawing attention to the way in which they are misperceived by others. Characters who seem to be unattractive or even sinister are shown to be brave and helpful, while characters who seemingly display strong moral and religious sentiments turn out to be deceitful and selfish.

Ezra Jennings is one example of a character who is initially presented in a negative light. When Franklin first encounters Jennings, he is struck by the man’s unusual appearance and Betteredge explains that, “nobody knows who he is—and he hasn’t a friend in the place” (331). Even at the very end of his life, Jennings resolves to “die as he had lived, forgotten and unknown” (470). Despite his unattractive aura, which leads to him leading a very isolated life, Jennings is clever, logical, and works doggedly to help solve the crime. His reclusive behavior is also partially explained because Jennings is dying of a painful disease and can only tolerate the agony by consuming regular doses of opium. Jennings does not allow his suffering to prevent him from serving a useful purpose, but his pain and isolation lead to him often being isolated and misunderstood.