Penelope Crook surprises Gabriel and the rest of the gang at the beginning of their second school year in Crookhaven with a stunning secret: deep beneath the lake lies an underground labyrinth that was once used for the toughest school exams. However, it was deemed too dangerous and was shut down and forgotten. But there are clues that the Nameless, the most ruthless criminal gang in the world, have taken advantage of it. The friends secretly follow this trail. Yet the path to the center of the labyrinth is fraught with seemingly insurmountable obstacles that test each of their rogue skills. They are confronted not only with all sorts of impossible puzzles but also with the question of how far they are willing to go to achieve their goal. Narrator Nico-Alexander Wilhelm takes us back into the mysterious world of the outlaws and through Gabriel's second school year filled with challenges and twists.