Firefighters make a grisly discovery of the body of 39-year-old wife and mother Carmella Knight after responding to a house fire outside Toronto. An elaborate undercover sting reveals a devious murder-for-hire plot.

Private Investigator and former police officer Taylor Wright vanishes, but detectives think there is more to the story after her girlfriend receives strange text messages from Taylor's phone.

After Florida teacher Denise Hallowell is found murdered in her home, investigators examine her family's tumultuous past in their desperate search for a killer.

An investigation into the poisoning of Wisconsin mother Julie Jenson takes a surprising turn when detectives learn that she wrote a letter days before her death pointing to a possible suspect.