Did you know there are roughly 25 active serial killers in the United States right now? Even though the chances of you meeting one are about the same as getting struck by lightning, it's fun to think about. In this edition of John Hinson's 100 Stories, you'll learn about 100 of history's most horrifying killers. Some names - like John Wayne Gacy or Ted Bundy - will be familiar, but you'll also be introduced to others who were arguably much more terrifying.