Cleo and Carla clash after Reese gets hurt while in Cleo's care. Weaver and Kovac cannot save the life of a developmentally challenged woman's only caregiver. Abby goes to a therapy session with Maggie. Later, Abby confesses to Maggie that she is afraid to bear children because they might be bipolar like her mother.

The ER is flooded with foster care home residents, attacked by a shooter bent on tracking down his son, who , with the help of Dr. Green, was put into the foster care system amid allegations he was being abused by his father.