When 41-year-old Peggy Carr suddenly fell gravely ill, doctors were stumped. Her symptoms made no sense—burning limbs, hair loss, and paralysis with no clear cause. But when her teenage son and stepson became sick too, investigators uncovered a chilling truth: the Carr family had been poisoned.

The substance was thallium—a deadly, nearly undetectable metal once used in rat poison. The discovery launched a full-scale forensic investigation that led detectives to a single suspect: a brilliant but disturbed neighbor with a background in chemistry and a fascination with murder.

This is the story of how science, persistence, and an undercover operation exposed one of Florida’s most shocking poison cases.

For a complete list of sources used in this episode, visit ForensicTales.com.

Forensic Tales is a Rockefeller Audio production.

Hosted by Simplecast, an AdsWizz company. See pcm.adswizz.com for information about our collection and use of personal data for advertising.