Stevenson depicts the hypocrisy of the Victorian Society. So, from this point of view, what Dr. Jekyll and Mr Hyde really is, is a fable, with a moral: "if one gives evil an inch, it will take a mile".

All around England, Stevenson saw that, although on the outside most noblemen seemed to be fine and upstanding citizens, inside they hid dark secrets. Many critics even suspect that Jekyll and Hyde was a self-admission by Stevenson of his own dark nature.Although often Dr. Jekyll and Mr. Hyde seems to be a tale of mystery and intrigue, Stevenson takes great pains to show that the evil Mr. Hyde is very deadly. There is certainly nothing comical about the trampling of the little girl on the street corner or the brutal slaying of Sir Danvers Carew. Jekyll’s dark side even causes death indirectly. Dr. Lanyon is shocked because of having witnessed the transformation from the good Jekyll to the evil Hyde. Here, Stevenson ventures to say that whenever anyone has the ability to see the evil side of man in its purest form, he will most certainly be fascinated by it.At first Satan’s net of evil seems fun and jocund. Dr. Jekyll admits this to Utterson in his letter, saying, "It seemed natural and human. In my eyes it bore a livelier image of the spirit, it seemed more express and single, than the imperfect and divided countenance I had been hitherto accustomed to call mine." Stevenson, using the dialogue of Jekyll, goes on to say that all people are a composite of both good and evil. He asserts, "...all human beings...are commingled out of good and evil." Here, Stevenson is leaving the narrow scope of his fictional tale, and indeed indicting all of society.Yet Stevenson’s story doesn’t have a happy ending. Indeed Satan’s dominance over the body of Dr. Jekyll eventually takes its toll. Jekyll is able to admit that after a few months of experimenting with Hyde, eventually the little man’s demands became increasingly extreme, seeking more and more power. Soon Jekyll has no control over Hyde, who appears by himself whenever Jekyll dozes off to sleep. He admits, "I was slowly losing hold of my original and better self, and becoming slowly incorporated with my second and worse." Finally Hyde causes Jekyll to commit the ultimate act of self-destruction: suicide.

Jekyll incriminates himself as the one to blame for the indivisible relationship with Hyde, and also tries to legitimate his experiments, but his error is that he uses this as excuses. The suicide is the result of the fight between Jekyll and Hyde, because Hyde is the one who administers the poison.