Moist von Lipwig, once a swindler and conman, is now unexpectedly in charge of the Royal Bank and Post Office, but life is about to get even more complicated. A revolutionary new invention—a steam-powered locomotive—captures the public’s imagination, with its creator, Dick Simnel, drawing crowds and stirring excitement. As the railway begins to take shape, ensuring that the trains run smoothly becomes a matter of national importance. Moist, who prefers words over hard work, quickly finds himself entangled in the chaos of overseeing a venture that involves rickety bridges, runaway cheeses, and even a tough "fat controller" with knuckledusters. Though he enjoys being alive, it becomes clear that some people will go to great lengths to stop this bold new era of transportation.