Sherlock Holmes is a fictional consulting detective created by Sir Arthur Conan Doyle. He is known for his astute logical reasoning, his ability to adopt almost any disguise, and his use of forensic science to solve difficult cases. Holmes is a loner, sociopath, and proud of his rational deductive process. His close friend and biographer, Dr. John Watson, often becomes his assistant in his investigations, and they share an apartment at 221B Baker Street. Holmes has a complex relationship with his brother, Mycroft, and consistently exhibits a disdain for the official police. His archenemy is the criminal mastermind, Professor Moriarty.