H.H. Holmes killing spree ran 1888-1894: anywhere from 9-200 murders (he confessed to 27 and only 9 were confirmed). He murdered people for insurance to start off with, but quickly moved to selling bodies as cadavers and bones to medical schools. He was almost a super villain with a "lair" dubbed "The Murder Castle" which was built by numerous contractors many who were hired to build a wall, a staircase, a room, and then immediately fired. This was done so that Holmes was the only person to know the layout of his Castle. In this "Murder Castle" there were airtight rooms where people could be gassed to death, trap doors, torture rooms, doors leading to nowhere, cremation furnaces, vats of acid, lime pits. During the 1893 World's Fair in Chicago, H.H. Holmes had his pick of hayseeds visiting the big city and lured them to his Murder Castle with the promise of rooms for rent. He was caught after a tip from a former cellmate set the coppers on his trail. Holmes was hanged by the neck until dead in a Philadelphia Prison in 1896 his final words were "Take your time old man" - directed to the executioner. He died after hanging for 15 minutes.