Fifteen-year-old Barnabas Bopwright is proud to live in the greatest city on earth. But under the shiny exterior lurks the hidden cost of the city's skyscraping success. On his way to school, Barnabas discovers a transit map with an unknown subway line. Soon he's on an impossible train, running from authorities who have guarded the city's dark mysteries for a century. The subway brings Barnabas to a hidden valley outside the city where he's...