Like most identical twins, the Spahalski brothers have a lot in common... but they may be the only identical twins who have both separately committed murder. Cuomo meets face-to-face with Robert Spahalkski inside a maximum-security prison where he's serving 100 years to life for four murders. The host confronts him with details of his crimes and tries to glean insight into the cause of his murderous urges. Could the desire to kill be a genetic trait? Cuomo tries to find some answers to the age-old question of nature versus nurture.

Jennifer Asbenson tells Chris Cuomo about her terrifying encounter with serial killer Andrew Urdiales. Even though she spent years telling people her story, not even her own mother believed her until Urdiales confessed to other crimes.

Chris Cuomo conducts the last interview that serial killer Andrew Urdiales will ever give. Was he insane? Did he hate women? What went wrong in his childhood to turn this man into such a monster?