The Strange Case of Dr Jekyll1and Mr Hyde is a novella written by Robert Louis Stevenson about a lawyer, Gabriel John Utterson, who investigates the strange link between his old friend, Dr Henry Jekyll, and the misanthropic man Edward Hyde. It was first published in 1886.

In his central theme of duality, "that strong sense of a man's double being which must at times come in upon and overwhelm the mind of every thinking creature", Stevenson had been inspired by a real life figure, Deacon Brodie, a respected member of the community by day, and a burglar by night.