"Forced to flee England and live in America in the 1890s, Professor James Moriarty returns to London in 1900 to find that his huge criminal empire, his 'family', has been infiltrated, raided and plundered by the coming crime boss, Idle Jack Idell. He also has evidence that one of his closest lieutenants, a member of his self-styled Praetorian Guard, is betraying him. Trying to reform his old family, tempting 'straying sheep' back into his fold, he engineers a plan to assassinate Idle Jack, but when things go horribly wrong, Moriarty is faced with an even bigger problem."--Publisher description.