When American inventor Benjamin Franklin arrives in Paris, he is upstaged by a compelling and enigmatic figure: Dr. Mesmer. In elaborately staged shows, Mesmer has Parisians believing he can control a magic force that changes the taste of water, cures illness, and controls thoughts! Can Ben Franklin's approach of observing, hypothesizing, and testing get to the bottom of Mesmer's tricks? A rip-roaring, lavishly illustrated peek into a fascinating moment in history shows the development of the scientific method -- and reveals the amazing power of the human mind.