Several lakes in North America would hide creatures as enigmatic as they are elusive. While their hypothetical presence arouses the derisive skepticism of the majority, some localities will nevertheless exploit this belief, because, as we have taught Loch Ness for almost 90 years, a monster can become a money-making attraction. But how to create a tourist activity from an imaginary being? Ultimately, even if the monster remains well hidden, it makes it possible to discover a region which, otherwise, would be less reported by tourists. It makes it possible to revitalize an often moribund economy in villages that have few resources. By keeping the monster alive, an entire community remains so.