Mary Ann Cotton

In the mid-1800s, Mary Ann Cotton is believed to have poisoned as many as 21 people with arsenic, many of them her own children. She left a trail of bodies behind her everywhere she went, but it was her cavalier remarks that finally drew suspicion.

Arsenic photo by SSPL/Getty Images

Topics in this Podcast: serial killers, forensics, england, Crime, biographies, women, 19th century, British history