The Sum of Her Parts (S03E05)

Years of enduring both verbal and physical abuse take a tragic turn when the victim finally retaliates against his tormentor. Unable to confront his mother, the disturbed man targets those who remind him of her. The team delves into the case, with Sam correctly identifying the killer's psychological issues, but she mistakenly believes he is directing his rage toward his wife instead of his mother. As the victims' ages increase, Sam recognizes her mistake and theorizes that the son is gathering the resolve to kill his abuser. The team races against time to locate the mother before he can carry out his deadly plan. Meanwhile, Sam realizes it's time for her and Chloe to start anew, prompting her decision to find a new home.