Mary Ann Cotton (S04E02)

Born in 1832, Mary Ann Cotton's tale is one of chilling Victorian-era homicide. She roamed the northeast of England, marrying solitary men, persuading them to secure life insurance policies, and subsequently poisoning them with arsenic. After their deaths, she would collect the insurance payouts. Her deadly actions extended beyond her husbands, as it is believed she also took the lives of 11 of her own children and stepchildren. Ultimately, it was Thomas Riley's determination that led to her capture, and Mary Ann Cotton was executed for the murder of her last victim, 10-year-old Charles Edward Cotton.