Appearing for the entire four-hour show, crime writer Philip Carlo discussed the mindsets of various types of killers such as mafia hitmen, serial killers, CIA assassins, and terrorists. All four types share certain traits-- they can remove themselves from normal human feelings, not thinking twice about committing murder, he said. They're also amazing actors who can make you believe that they're your friend, he added. Carlo considers terrorists to be the most "successful" of the four groups, as they've spread fear on a worldwide basis.

Many killers underwent brutal abuse during the ages of 1 to 8, and manifest sociopathic tendencies in their early teens. Serial killers, in contrast to assassins, experience sexual pleasure from their crimes, he reported. Female assassins are the most feared, because you never suspect they're coming, he said.

He discussed the Mafia hitman, Richard "Ice Man" Kuklinski, whom he visited for many hours in prison. At nearly 6' 6" and 320 lbs., he was also called "The Big Guy," and reportedly eliminated over 200 people in a "career" that spanned four decades. A virtual "killing robot," he worked as an independent contractor for seven different crime families and had no qualms about carrying out torture along with murder, if so assigned. In one instance, he was said to leave a man trapped in a cave filled with rats.