"The Strange Case of Dr. Jekyll and Mr. Hyde" (commonly known as "Dr. Jekyll and Mr. Hyde") is by the Scottish author Robert Louis Stevenson and first published in 1886. It is about a London lawyer named Gabriel John Utterson who investigates strange occurrences between his old friend, Dr. Henry Jekyll, and the sinister Mr. Edward Hyde. ¿ ¿The work is known for its vivid portrayal of a split personality, split in the sense that within the same person there is both an apparently good and an evil personality each being quite distinct from the other. The novella's impact is such that it has become a part of the language, with the phrase "Jekyll and Hyde" coming to mean a person who is vastly different in moral character from one situation to the next.