The Salem Witch trials of 1692 imprisoned more than 150 people, with 19 hanged. Centuries later, a plausible, natural explanation has emerged for symptoms exhibited by those said to be bewitched. Behavioral psychologist Linda Caporeal takes viewers on a journey from wrenching convulsions and vivid delirium to contaminated crops, hallucinogenic drugs, and an ancient bog man hacked to death. Her theory may finally solve the witches' curse.