Well, 'The Picture of Dorian Gray' can be considered in this category. Dorian's inner decay while his outer appearance remains beautiful is like a form of duality. Then there's 'American Psycho'. Patrick Bateman is a character who has a normal - seeming exterior but harbors extremely violent and deranged thoughts and actions, much like the Jekyll and Hyde idea. And 'Secret Window' also has elements of this, as Mort Rainey seems to have a split in his personality that leads to some disturbing events.
Basically, the tale of Jekyll and Hyde centers on Dr. Jekyll's experiments with a concoction that leads to his transformation into the evil Mr. Hyde. It delves into the darker side of human personality and the consequences of unleashing it.
The 'Jekyll and Hyde' story is centered around the concept of split personality. Dr. Jekyll represents the civilized, good - natured side. He's a man of science, respected in society. However, when he becomes Mr. Hyde, it's like a completely different being emerges. Hyde is brutish, immoral, and has no regard for the norms of society. This transformation is not just physical but also mental and moral. The story explores the consequences of trying to tamper with the fundamental nature of human duality.
Well, basically, Dr. Jekyll has a hidden side that emerges when he takes a special concoction. This side is the evil Mr. Hyde. The story delves into the conflict and mystery of this transformation and its consequences.