In 2013, an inhabitant of Cagnes-sur-Mer, France, found a land flatworm in his garden and had the good idea to send the photograph to a network of naturalists. We then launched a citizen science survey in France to learn more—and we were not disappointed. More than 10 species of land flatworms from elsewhere are now reported in metropolitan France, including a giant species 30 centimeters long and a species that is now found in more than 70% of France's departments.