The Strange Case of Dr. Jekyll and Mr. Hyde, written by Robert Louis Stevenson, is a classic gaslamp fantasy novella that explores the duality of human nature. The story follows Dr. Jekyll, a respected scientist, who creates a potion that transforms him into the sinister Mr. Hyde. As Dr. Jekyll struggles to control his alter ego, the narrative delves into themes of morality, identity, and the consequences of unchecked desires. With its enduring popularity and psychological depth, The Strange Case of Dr. Jekyll and Mr. Hyde remains a seminal work in the gaslamp fantasy genre.