"The Seventh Tower" is a fantasy series written by Garth Nix. It follows the story of a young boy named Tal, who lives in a world divided into seven towers. Each tower has its own unique powers and characteristics, and the inhabitants rely on a magical light source called the Light to survive. As Tal embarks on a quest to save his family and uncover the mysteries of the towers, he faces various challenges and encounters different characters, including the Shadow and other tower dwellers. The series explores themes of bravery, friendship, and the struggle between light and darkness.