In 1974 there was a killer on the loose who's MO was to bind, torture, and kill. The killer evaded law enforcement for years even taking long hiatuses in between killings to play the role of a devoted family man. But, behind the scenes he was brutally murdering men, women, and children. This killer was known as BTK.........

Sources;

https://en.wikipedia.org/wiki/Dennis_Rader