Born in a small village in eighteenth-century France, Jeanne Villepreux wasn’t expected to transform marine science. Curious, creative, and clever, Jeanne ventured to Paris by foot as a teenager. After achieving acclaim as a seamstress, she met a wealthy merchant and traveled with him to Sicily, where they married. Rather than settling into a life of domesticity on this beautiful island, she set out to investigate its natural wonders, from fossils and insects on land to the marvelous mysteries of the sea. In an era when women weren’t accepted into scientific societies and many naturalists based their findings on dead specimens, Jeanne fashioned her own fortune. She observed and experimented on living animals, in particular one very unusual shelled octopus called an argonaut. To keep argonauts and other sea creatures alive long enough to learn from them, she invented a device to hold them—the aquarium. With patience and persistence, she solved the two-thousand-year-old mystery of whether argonauts grow or steal their shells, and she made sure the scientific world knew about it. Author and octopus enthusiast Danna Staaf presents an engrossing look at the life and science of Jeanne Villepreux-Power, showing how this remarkable woman helped bring about a sea change in the study of marine life.