It's not easy being a heroine inside a story that no one is reading.But Princess Sylvie has an even bigger problem: By chance, she and the other characters from The Great Good Thing and Into the Labyrinth find themselves launched into outer space bound for the moons of Jupiter Here they must learn to act out their book's plot while floating weightlessly through the pages.If life is bizarre for Sylvie, it turns grim for the astronauts when their spaceship...