In a Shellworld - a vast, ancient artificial planet of nested levels, each home to a different civilisation - a king is murdered and his eldest son Ferbin is forced to flee. His younger brother Oramen is left behind, at the heart of a court he is only beginning to learn how to read. Their sister Djan Seriy Anaplian left this world years ago and became something else entirely: an agent of the Culture's Special Circumstances. Now she must return to a place she thought she had abandoned, concealing abilities that would be incomprehensible to the people she grew up among. A novel about the collision between civilisations at vastly different levels of development, and about what you owe the place you came from.