James Moriarty

Lore & Background

Moriarty is an extremely tall, thin man with a pale, ascetic face and shoulders rounded from much study. His forehead domes out in a white curve, his eyes are deeply sunken, and his face protrudes forward, oscillating side to side in a "curiously reptilian fashion." He believes in phrenology, once telling Holmes he had "less frontal development than I should have expected." Born with excellent education and a phenomenal mathematical faculty, he wrote a treatise on the Binomial Theorem at age 21, earning him a university chair. However, "dark rumours" forced his resignation. In London, he works as an army coach before becoming a consulting criminal mastermind. He does not commit crimes himself but orchestrates them, offering plans and protection to criminals in exchange for obedience and profit shares. Holmes describes him as the "organiser of half that is evil and of nearly all that is undetected" in London.

In Their Own Story

In "The Adventure of the Final Problem," set in 1891, Holmes reveals to Watson that isolated crimes are actually Moriarty's machinations. After confronting Holmes personally with a death threat, Moriarty learns the detective has delivered evidence to the police. Knowing his lieutenants intend to kill Holmes before arrest, he follows the detective and Watson to Switzerland. Their pursuit ends at the Reichenbach Falls. Watson arrives later to find signs of hand-to-hand combat on the cliff edge, concluding both men fell to their deaths, though only a goodbye note from Holmes remains, which Moriarty allowed him to write before the battle. In "The Valley of Fear," set earlier but written later, Holmes attempts to stop Moriarty's men from committing murder. A policeman mentions Moriarty owns a painting by Jean-Baptiste Greuze called La jeune fille à l'agneau, which Holmes notes could not be bought on a professor's salary.

Reader's Guide

Moriarty is characterized as ruthless, vowing that if Holmes brings destruction upon him, he will do the same. He respects Holmes's intellect, calling their struggle an "intellectual treat," yet he makes numerous attempts on the detective's life through agents like Colonel Moran. His methods include stage-managing deaths to look like accidents, such as falling masonry, speeding vehicles, and a man lost overboard at sea. In "The Empty House," Holmes reveals Moriarty commissioned a silent air gun from a blind German mechanic named von Herder for Moran to use. While Doyle intended "The Final Problem" to be the end of Holmes, public pressure brought the detective back; however, Moriarty's death remained permanent. Consequently, The Valley of Fear is set before his fall but features him as an active villain.

Did You Know?

• Moriarty was based partly on Adam Worth, a real-life criminal mastermind whom Doyle met via a Scotland Yard inspector's description.
• In "The Final Problem," Watson initially tells Holmes he has never heard of Moriarty, despite later claiming to know him as the "famous scientific criminal" in the earlier-set novel The Valley of Fear.
• Moriarty authored a highly respected work titled 'The Dynamics of an Asteroid' before resigning his university post due to dark rumours.
• Holmes mentions that Moriarty prefers organizing lethal accidents, such as making targets appear lost overboard or crushed by falling masonry.