"I never would have guessed in a million years," said Carole Nelson, a member of the Christ Lutheran Church, where Dennis Rader, then suspected, now convicted "BTK" killer, served on the church council.

How often do we hear such comments from bewildered friends, neighbours and associates when they discover that an individual in their midst turned out to be a serial murderer?

Dennis Rader.

Who would have suspected jovial building contractor, civic leader, and active political participant, John Wayne Gacy? Who would have believed that he had been burying body after body in the crawlspace of his suburban Chicago home? Or Ted Bundy, with his air of sophistication and handsome appearance? Why would he be out systematically destroying attractive young women and girls? Computer-programmer Randy Kraft - how could he have sadistically slain up to 67 young men? Friendly builder Fred West - torturing for days on end before extinguishing his helpless victims? …