n 1974, the BTK serial killer terrorised the people of Kansas. Known for binding, torturing and killing men, women and children, he taunted police with his letters for 5 years before mysteriously disappearing in 1979. 10 murders and 25 years later, he still wasn’t found. This is the story of the longest running serial killer case in history. What this documentary doesn’t say is that B.T.K. was caught in 2005.