Before he was Sherlock's rival, Moriarty fought against the unfair class caste system in London by making sure corrupt nobility got their comeuppance. But even the most well-intentioned plans can spin out of control--will Moriarty's dream of a more just and equal world turn him into a hero...or a monster?

When the queen herself hires Sherlock Holmes to arrest the Lord of Crime, Sherlock sets out to save William instead. Unfortunately, William fully intends to complete his purification of the British Empire--at the cost of his own life. As the Moriarty Plan inches toward its inevitable conclusion and the Great Detective faces off against the Lord of Crime, both men will reveal the innermost depths of their hearts against a backdrop of London in flames.