World's only consulting detective, a profession he created for himself. Based in London and often consulted by Greg Lestrade of New Scotland Yard, usually taking his best friend and flatmate, John Watson, on cases. Has a keen and strong interest in unusual or bizarre crimes. A thinker and an observer, has the ability to notice and draw deductions from seemingly trivial details. Has an unusual and somewhat anti-social personality. Often utilizes his "mind palace", a tool for remembering.