Foul Play: A Historical True Crime Podcast · Shane L. Waters, Wendy Cee, Gemma Hoskins

Geneva: The Poisonous Nurse

November 18, 2025·31 min·5 clips

The story begins with a glass of lemonade in Geneva's Plainpalais district and a young woman whose body turns against her within moments. Her pupils dilate grotesquely. Her heart pounds. The room tilts into delirium. A doctor is summoned, spots the signs of belladonna poisoning, and sees that this is not ordinary illness. His decision to run to the cantonal hospital saves her life. That rescue also opens the door to a larger investigation. Marie-Gina Ray emerges as a nurse who used the trust people placed in her for something far darker. By the story's account, she had already poisoned at least six people to death and attempted to murder perhaps 30 more. The story also explains that morphine was used legitimately in 1860s medicine for pain relief, but in excessive doses it suppresses breathing until the victim simply stops inhaling. From the outside, the death can look almost peaceful. The victim may appear to be sleeping. The story shows how both drugs could be hidden inside food and drinks without raising suspicion. Sweetened water, lemonade, candy, and bonbons all became delivery systems. Children received little candies. Adults were offered refreshing drinks. Because she worked as a nurse, she had professional cover for preparing medicine, mixing drinks, and measuring out medications. The story also lays out her slower strategy. Low doses could mimic illness, produce brief recoveries, and leave a medical trail that looked careful rather than criminal. Her notes helped maintain the appearance of competence while the deaths accumulated around her. The closing turns the case back toward the people who should have been protected and the warning signs that were ignored: frightened children, attentive doctors, repeated deaths, and a caregiver who kept showing up at the center of them.

As heard by us

A poison case that keeps its eye on the victims and the warning signs, not just the killer.

The episode starts in Geneva in 1868, with Marie-Catherine Fretz accepting lemonade from her new friend, the nurse Marie-Gina Ray, and the story turns dark quickly.

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Why you'd press play

Press play if you want a Geneva poison case where care becomes cover.

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