Perry Smith (Robert Blake) and Richard 'Dick' Hickock (Scott Wilson) plan to rob a farming family they perceive as wealthy. But when they break in the home and wake all the family members, they discover there is very little cash in the house. They decide to murder all four members of the family. The two criminals escape to Mexico, but are brought to justice by police investigator Alvin Dewey (John Forsyth). As the two criminals await trial and punishment Dewey and Jensen (Paul Stewart), a journalist, discuss what they have uncovered about the men's tortured backgrounds in an attempt to understand what would lead the two drifters, who had no other motive than money, to kill innocent people. They wait to see if execution will be finalized and discuss society's role in dealing with such a crime and the controversy of capital punishment.