In this first episode, Piers travels to Gatesville Texas to meet Erin Caffey who, at the age of 16, masterminded the brutal murder of her entire family. For this incomprehensible act, Erin will remain behind bars until she is almost 60 years old and in a gripping encounter behind bars, Piers draws from Erin what made an apparently typical teen-aged girl conspire with her boyfriend to kill her mum, dad and two younger brothers.

In this second episode, Piers meets two very different female murderers, both of whom killed someone they loved.