Professor Moriarty

Illustration of Professor Moriarty by Sidney Paget

Professor Moriarty a.k.a James Moriarty is a character in the stories written by Sir Arthur Conan Doyle. The archenemy of Sherlock Holmes, Moriarty is a criminal mastermind whom Holmes describes as the "Napoleon of crime". Doyle lifted the phrase from a real Scotland Yard inspector who was referring to Adam Worth, one of the real life models of Moriarty. The character of Moriarty as Holmes' greatest enemy was introduced primarily as a narrative device to enable Conan Doyle to kill off Sherlock Holmes, and only featured directly in two of the Sherlock Holmes stories. However, in more recent derivative work he has been given a greater prominence and treated as Holmes' primary antagonist. Moriarty vows that Holmes faces inevitable destruction if he continues to meddle in Moriarty's plans. Moriarty has full respect for Holmes' intellect and says that it has been an intellectual treat to grapple with him but is also completely willing to kill Holmes should he oppose him any further, showing a ruthless side.
He has a fiery temper, furiously elbowing aside people in the train station when Holmes escapes him. Moriarty also has a vengeful streak, pursuing Holmes to Switzerland to kill him for destabilizing his organization. Despite the vast crime ring over which he presides, Moriarty is fiercely independent. When his men fail to kill Holmes, he pursues Holmes by himself, whereas Holmes takes Watson with him wherever he goes. The only individual who appears to have Moriarty's complete confidence is his henchman Colonel Moran.
Sherlock described Moriarty as:
'He is a man of good birth and excellent education, endowed by nature with a phenomenal mathematical faculty. At the age of twenty-one he wrote a treatise upon the binomial theorem which has had a European vogue. On the strength of it, he won the mathematical chair at one of our smaller universities, and had, to all appearances, a most brilliant career before him. But the man had hereditary tendencies of the most diabolical kind. A criminal strain ran in his blood, which, instead of being modified, was increased and rendered infinitely more dangerous by his extraordinary mental powers. Dark rumours gathered round him in the University town, and eventually he was compelled to resign his chair and come down to London. He is the Napoleon of crime, Watson. He is the organiser of half that is evil and of nearly all that is undetected in this great city...' - Sherlock Holmes
A point of interest is that the "high, domed forehead" was seen as the sign of a prodigious intellect during Conan Doyle's time. In giving Moriarty this trait, which had already appeared in both Sherlock Holmes and the detective's brother Mycroft, Doyle may have intended to portray Moriarty as a man having an intellect equal or greater than that of Holmes, and thus the only man capable of defeating him. Moriarty died when he fell off the Reichenbach Falls while Holmes, as revealed in "The Empty House", only faked his death to make the few remaining Moriarty henchmen expose themselves.