Adler of Sherlock Holmes is a character from the famous detective stories written by Sir Arthur Conan Doyle. She is Irene Adler, a professional adventuress and former opera singer who appears in the first Sherlock Holmes novel, A Scandal in Bohemia. She is considered to be one of the most intelligent and resourceful female characters in literature. Doyle's SLEUTH, Sherlock Holmes, is known for his remarkable deductive powers and Adler is one of the few people who can outwit him.