The evil Abusive Mother
The unnamed Abusive Mother is a villainess from "Monsters", episode 3.06 of 9-1-1 (airdate October 29, 2019). The episode took place on Halloween, with one of the opening scenes showing a young girl named Bethany arriving at a man's house. Although the man thought she was a trick or treater, Bethany collapsed in his door leading to him calling 9-1-1.
Athena Grant was on the case after it was revealed that Bethany showed signs of extreme abuse and starvation. Upon learning that no-one in the neighbourhood had ever seen her before, Athena investigated a house without any Halloween decorations. There, she made the shocking discovery of several more children chained up in the house's basement.
After the other children were rescued, it was learned that their parents were religious fanatics who hid their children from the rest of the world and forced them to live under squalid conditions. At that moment, the couple arrived back at their home and demanded to know what was being done with their children, with the evil mother revealing they had been out searching for Bethany. Athena blasted the villainous couple for their abuse of their own children, adding that their kids would be going to the hospital and they would be going to prison before having officers arrest the evil woman along with her husband.