Swiss man servant led a double life as a calculating serial killer who roamed the streets of London killing prostitutes fifty years before Jack the Ripper terrorised the city
http://www.dailymail.co.uk/news/article-4112912/How-Swiss-gentleman-servant-led-double-life-calculating-serial-killer-roamed-streets-London-killing-prostitutes-fifty-years-Jack-Ripper-terrorised-city.html