Henry Jekyll is a doctor and experimental scientist and, on the surface, he is wealthy and respectable. He has a reputation for being a friendly and sociable person with a group of friends which include the lawyer, Utterson, and another doctor, Hastie Lanyon. He was born to a respectable family and was well educated but from an early age had engaged in many ‘youthful indiscretions’ which he enjoyed but was careful to keep them a secret. As an aspiring doctor and respectable gentleman Jekyll realised that he risked professional ruin and scandal unless he modified his behaviour, so he repressed his darker side and led a regular life of respectability. When we meet him in the story he is a middle-aged man fascinated with the theory that every man has a "good" side and a "bad" side, and he has decided to investigate the theory, hoping to rid himself of his dark impulses forever. His investigations are successful and he creates a potion which personifies the "evil" in a person in the form of an completely different human being. This new, monstrous creation has no goodness or moral code and can commit acts of evil without remorse; furthermore, upon drinking the same potion it could then be transformed back into the original person. Edward Hyde is the personification of Jekyll’s “bad” side, a man capable of committing a number of crimes including the violent abuse of a child and the vicious unprovoked murder of the elderly Sir Danvers Carew. Jekyll's obsession with Hyde grows out of his control and Hyde begins appearing whenever he wants to — and not at the command of Dr. Jekyll. Jekyll cuts himself off from the outside world and lives in his laboratory in a constant state of anxiety, trying but failing to control Hyde. Finally, traumatised by guilt, anxiety and a lack of sleep he commits suicide just as Utterson and Poole break down the laboratory door. As Jekyll is dying, Hyde appears, and it is the body of Hyde which Utterson and Poole discover. Henry Jekyll

Hyde, as his name indicates, represents the hidden dark side of mankind. Hyde represents the embodiment of pure evil; When we first encounter him, he tramples a young girl in the street. His presence creates feelings of fear, antagonism, and loathing in other people. In the scene where he pays compensation to the girl (and in other times in the story) people react with horror. Just the sight of him seems to stir within people a feeling of terror and a deep desire to commit violence. Indeed, the mere presence and appearance of Edward Hyde brings out the very worst evil in other people. As Hyde represents the evil in man (or in Dr. Jekyll), he is, therefore, symbolically represented as being much smaller than Dr. Jekyll — Jekyll's clothes are far too large for him — and Hyde is also many years younger than Jekyll. This could suggest that the good in humanity outweighs the bad or that the evil side of Jekyll did not develop until later in life. As the story unfolds, Hyde's acts become increasingly horrific climaxing in the murder of Sir Danvers Carew. Hyde clubs Carew to death for absolutely no reason other than the fact that Sir Danvers appeared to be a good and kindly man — and pure evil despises pure goodness. Since Hyde symbolises the evil or perverse side of Jekyll, and since Jekyll does, vicariously, get pleasure from the degradations which Hyde commits, Hyde gradually begins to take control of the good Dr. Jekyll. A conflict within Jekyll erupts which ultimately results in Jekyll’s suicide – his final desperate act to get rid of Hyde. As Jekyll dies he transforms once again into Hyde, and it is the body of Hyde that is discovered by Utterson and Poole when they break down Jekyll’s laboratory door. Edward Hyde

Mr Utterson is an old friend of Jekyll, and his lawyer. He is calm and logical and as a lawyer he believes in the rational world rather than the supernatural one. Like a scientist or a police investigator Utterson gathers evidence throughout the story. He attempts to solve the mystery by weighing up the evidence and coming to a reasonable conclusion. Utterson is 'a lover of the sane and customary sides of life’ and he is employed by Stevenson to represent the attitudes and viewpoints of the average Victorian man. However Utterson is not immune to irrational feelings and impulses. When he first meets Hyde he reacts in an irrational way: 'not all these points together could explain the hitherto unknown disgust, loathing and fear with which Mr Utterson regarded him.’ However for the majority of the time Utterson is clear headed and scientific in his deductions and ideas. Utterson is a good man. He spends a lot of time and effort attempting to help and advise Jekyll. Jekyll recognises that he is a good friend, but rejects all his offers of help as he realises that his problems are of the sort that Utterson would not be able to understand or help to resolve. Utterson is observant and inquisitive but at no point does he suspect Jekyll and Hyde are the same person. His rational view of the world makes such a conclusion preposterous which is why, even when he discovers that Hyde's and Jekyll's writing is strangely similar, Utterson draws a reasonable but wrong conclusion: that Jekyll has forged Hyde's handwriting to cover for him. In Chapter 8, Utterson disappears from the story as he goes home to read the documents found in Jekyll's laboratory. The novel ends with two chapters containing the two documents he goes home to read. The reader never discovers how Utterson reacts to the shocking news that the documents contain. We don’t know if he is taken ill like Lanyon or if changes his previously held beliefs or whether he refuses to believe what would be an incredible story in his rational eyes. He is left as an uncompleted character. Maybe Stevenson does this to suggest that reason and logic cannot provide us with all the answers to life’s mysteries. Gabriel Utterson

In contrast to Jekyll, the "metaphysical" and experimental scientist, Lanyon is a "traditional" scientist — completely uninterested in the supernatural. As young men, Lanyon and Jekyll were close friends, but when Jekyll became obsessed with the darker aspects of science, the friends disagreed and fell out — about ten years before the story begins. Utterson questions Lanyon about Jekyll but Lanyon is very reluctant to reveal too much, only stating that Jekyll is interested in the ‘perverse’ aspects of science, and for that reason, he no longer speaks to him. As Jekyll’s decline takes hold he decides to reveal himself to Lanyon. This may be done to prove to Lanyon that Jekyll’s experiments were not ‘scientific balderdash’ or to punish Lanyon for his priggish condemnation of Jekyll. Whatever the reason, Hyde arranges a transformation to occur before the good doctor Lanyon. Lanyon is so horrified at what he see that he falls ill. He cannot cope with the fight between his common- sense view of the world and what Jekyll's experiments reveal. "I ask myself if I believe it, and I cannot answer. My life is shaken to its roots." A few weeks later, the doctor is dead of shock. Dr Hastie Lanyon