Every parent's worst nightmare is the possibility that their child has the same evil traits as the most heinous murderers. In this episode, specialists look at the early warning indicators in psychopathic killers arrested as teenagers and young adults.

A disgruntled man decides that killing someone will make him feel better, so he chooses a random stranger and uses nine rounds to ruin two families' lives. Next, an egotistical kid attempts to persuade investigators that he beat a senior citizen to death in self-defense.