Tor, undercover security operative for the British Jockey Club, masquerades as a waiter on a horse-racing junket called the Great Transcontinental Mystery Race Train.
As winter approaches the animals take the train to the Southern forest, but when they realize that Squirrel has missed the train, they turn back to rescue him from the cold and snow.
When they travel by train across America, Christina, Grant, Mimi, and Papa find themselves facing mysterious mishaps, spooky surprises, and treacherous tunnels.
Jack, a railroad switchman, frantically tries to save an ant who is heading east on a westbound track, straight into the path of an oncoming freight train.
