On December 14, 1955, Darrel Parker arrived at his Lincoln, Nebraska, home to find his wife, Nancy, strangled to death. Although their house was broken into less than a month earlier, the police were unable to find any leads, so their attention turned to Parker. To make their case, the authorities relied on a private interrogation by polygraph operator John Reid of Chicago. Reid's company, founded in 1947, today provides interviewing and interrogation techniques that the company claims are the most widely used in the world.

Barbarous Souls tells the story of Darrel Parker's...