He didn't kill anyone and he's even claimed he never ordered his followers to kill anyone. Was Charles Manson a murderous mastermind or the mentally ill scapegoat for a group of drug-addled kids who got in way over their heads?

The Unabomber's reign of terror lasted for 17 years and sparked the biggest manhunt in FBI history. But what drove math prodigy Ted Kaczynski to murder?

Why the motives for the Columbine High School shooting had nothing to do with bullying or revenge — and why the real truth is even more disturbing.

From the days of the sword through the advent of the guillotine, Charles-Henri Sanson killed some 3,000 people during his bloody career.