S4, E20: When a ten-year-old girl is reported missing by her schoolmate, briscoe and logan embark on an investigation that uncovers a sad reality: removed from the custody of her alcoholic natural mother, children's services negligently placed her with a foster mother who treated the child as a slave. The physical abuse that the girl suffered at the hands of her foster mother's boyfriend did not prompt children services to remove her from the situation. The trail ultimately leads the detectives to the girl's former teacher, a wealthy, eccentric woman who, after the devastating loss of her own child, has sought to fill the void by becoming the savior of misfortunate children. In her effort to rescue the girl from the system, the teacher hid the child in a secret room in her basement, where she provided love, attention, and a stable home.