From 1974 – 1971, a serial killer tormented the people of Kansas. He called himself BTK, which stood for BIND, TORTURE, KILL. He wanted to incite fear and panic, and so his killings were especially brutal. He taunted police with postcards, letters, and voice messages, but no matter how many clues the madman gave them, they still couldn’t catch him. But then, in 2005, after 10 murders and more three decades of terrorizing the locals, they got him. And suddenly it was clear how he’d managed to hide in plain sight for so long.