On April 26th, 1871, a police constable walking one of London's remotest beats stumbled upon a brutalized young woman kneeling in the muddy road, her face smashed and battered. The policeman gaped in horror as the woman stretched out her hand to him, collapsed in the mud, muttered "let me die," and slipped into a coma. Five days later, she died, her identity still unknown. Within hours of her discovery, scores of Metropolitan Police officers were...