One of the earliest and most enduring criticisms of Stevenson—that he wrote only children’s books—has perhaps arisen from confusion about his method. Although his essays, adventure and travel stories, and poems all demonstrate an ambition to produce serious and important art, the childlike imagination that infuses all of his works has been misperceived by some as merely childish. The fact that Stevenson, as an adult, had the ability to recapture the emotions and sensations of childhood and at the same time explore the ambiguities of human motivation made him a powerful and imaginative writer.

The Strange Case of Dr. Jekyll and Mr. Hyde is a serious romance, a genre usually intended for the instruction of the young. As a writer of romances—nineteenth century stories depicting the truth of the human heart—Stevenson successfully adapts a novel about adults into a thriller that challenges young people to consider the ambiguity of human nature. He was interested in psychology, and he excels at penetrating façades and exposing the ambiguities underneath them. The several narratives that tell the story of Jekyll and Hyde present differing views of reality and prepare the reader for the chief ambiguity in the novel—Jekyll’s attitude toward Hyde. Stevenson uses extensively the idea of the double, or Doppelgänger—the theory that an individual’s character is composed of two parts, a reasonable self and evil twin or shadow, which are constantly at war—that forms the split center of The Strange Case of Dr. Jekyll and Mr. Hyde. Yet, Jekyll and Hyde (Jekyll’s double), although split, are not two. Sharing one body and one brain, they do not separate but assume a change in form in which Jekyll is replaced by Hyde, who was within Jekyll.

Jekyll, whose existence makes Hyde possible, has rejected Hyde for more than twenty years—the chemical potion representing only his most dramatic step. Hyde is slowly transformed from one who tramples a child impersonally and without conscience to a selfish, cruel creature who is consumed with malicious hatred of Jekyll. Meanwhile, Jekyll continues his dissociation from Hyde. He considers the possibility of destroying Hyde altogether, accelerates his performance of altruistic deeds, and refuses to acknowledge Hyde as a portion of himself. Hyde is enraged at his treatment by the person to whom he owes his life, and he becomes increasingly evil. He assumes control at will, and Jekyll, failing to understand that what he had attempted was an impossibility, continues to believe that the experiment could succeed if he could only obtain pure powder for the potion. In desperation, Hyde commits suicide, thus destroying both men.

To strengthen his theme—the essential ambiguity and unknowable nature of the self—-Stevenson layers contrasts within the various points of view that form the narrative. The friendship of Enfield, the first narrator, and Utterson is mysterious, because they are almost polar opposites. The motif of the double, suggested by their regular and almost compulsive walks through the fog-shrouded streets of London, continues in their responses to Edward Hyde. Although both regard Hyde himself with intense disgust and nausea, the mystery of Hyde’s identity provides a mere anecdote for Enfield, while Utterson finds it very troubling. For Dr. Lanyon, who is more closely associated with Jekyll, the knowledge of Jekyll and Hyde is fatal.

The phrase “Jekyll-and-Hyde” does not merely denote a kind of split personality, but rather refers to Jekyll’s intense conflict within himself. Stevenson presents to young readers an extreme case that nevertheless illustrates the dangers of refusing to accept duality as a fact of human nature.