In the fall of 1888, all of London was held in the grip of unspeakable terror. An elusive madman calling himself Jack the Ripper was brutally butchering women in the slums of London’s East End. Police seemed powerless to stop the killer, who delighted in taunting them and whose crimes were clearly escalating in violence from victim to victim. And then the Ripper’s violent spree seemingly ended as abruptly as it had begun. He had struck out of nowhere and then vanished from the scene. Decades passed, then fifty years, then a hundred, and the Ripper’s bloody sexual crimes became anemic and impotent fodder for puzzles, mystery weekends, crime conventions, and so-called “Ripper Walks” that end with pints of ale in the pubs of Whitechapel.