Strange Case of Dr. Jekyll and Mr. Hyde

The Strange Case of Dr. Jekyll and Mr. Hyde by Robert Louis Stevenson is a novella written during the late 19th century that delves into the duality of human nature and the struggle between good and evil. 
The narrative follows Mr. Utterson, a lawyer, as he investigates the mysterious relationship between his friend, Dr. Jekyll, and the sinister Mr. Hyde, uncovering dark secrets that test the boundaries of morality.