A thousand years after a war between psychic and non-psychic humans reshaped the world, Saki Watanabe lives in a village that presents itself as peaceful, where children are schooled in Cantus, a telekinetic power drawn from thought, as soon as it awakens in them. When Saki and her classmates break a strict rule forbidding them from learning their society's real history, they uncover truths about the violence their ancestors committed and buried. The original novel, winner of the 29th Nihon SF Taisho Award, is the source behind the later manga and anime adaptations of Saki's story.