From the screenwriter of Academy Award--nominated Puss in Boots and Puss in Boots: The Last Wish comes an inventive middle grade adventure about an interdimensional school for time travelers perfect for fans of the Spy School and Mr. Lemoncello's Library series. When Bertie Wells accidentally creates a black hole in his bedroom in the year 1878, it's the very last thing he expects--except maybe the grown-up who steps...