Dangerous madmen or divinely inspired prophets? From murdering religious sects like the Assassins and the Thugs, to the orgies of the little known Khlysty and the self-mutilations of the Skloptzi; including modern day killers like the vicious Manson Family and the violent racism of the Ku Klux Klan - this book shows how cults and fanatics had such a powerful effect on the world.