Terry should never have been in the middle of Crow Wood that night - then the Torus couldn't have taken him. But he was, and it did. Now he finds himself in a strange new world, with no hope of getting home again unless he can find the seven tumblestones. New friends Gwen, Meeshka and Polka will help him solve the riddles, left by the mysterious Stranger - but the Baron's secret police are closing in fast. The key to the mystery lies in the mountains of the far north, where the 'Watcher' is waiting. The friends set out on their desperate quest, but it soon becomes clear that there is a deeper mystery behind the hiding of the stones, and an even deadlier enemy is just waiting for its chance.