When two Midwestern families with no clear connection to each other are killed just miles apart, the team is called in to find the family annihilator before he strikes again. At first, they are stumped: it seems that both sets of parents let the killer into their house, fed them dinner, and even left them alone with their children without any fear of danger. It's not until the third body – that of Minister Louis Hannum – is discovered dead in his truck on the side of the road that the team figures out that the UnSub is actually a young teenage psychopath. The BAU team discovers that he was left at a hospital in Omaha by his fearful mother due to a misunderstanding of a loophole in the state’s safe haven law, which at one point allowed parents to abandon any child under 18 and have them become a ward of the state. Now, young Jeremy Montgomery is killing his way home - where he will attempt to exact his final revenge on the mother who left him behind.
Meanwhile, young Ellie (Ep. 601) has run away from her foster home and flown to DC in the hopes that Morgan can find her a better place to live. With some help from Garcia, he manages to secure a hearing with Child Protective Services to transfer her to Virginia so she can be closer to him.