Rarely does a childhood memory carry the weight of the supernatural quite like this one. In a hair salon in early 2000s Massachusetts, a psychic reader named Celestine shared a chilling tale from her childhood—a story that changed her life forever—a story rooted deep in the folklore of 1950s rural Trinidad.

When Celestine was just nine years old, she defied her grandmother’s warnings and visited a woman the village feared. She recounted the legend that was Mama Vashti, a mysterious woman living isolated in the village who possessed supernatural knowledge of remedies and spiritual practices. Though villagers secretly sought her help for love and prosperity spells, they avoided her publicly, whispering that she was a soucoyant—a shape-shifting creature from Caribbean folklore who sheds her skin at night. Whatever sh ...