Richard journeys with his wife to a realm where he can meet himself as he'll be twenty years from now, where he can talk face-to-face with the person he was in the past, in parallel lifetimes, and in alternate worlds.

Kate and Tom are now full-fledged conductors of the steam-powered, animal-saving Great Secret Intercontinental Railway, but when Kate takes the Silver Arrow out on an unsanctioned mission to find Uncle Herbert she discovers a mysterious train called the Golden Swift with an agenda of its own.