And the earth's climate is much changed -- it's colder than ever before in the north, and unbearably dry and hot in the south. Mara, who is seven, and her four-year-old brother Dann find themselves somewhere very strange, not home, getting used to all these new names...They are taken in by a kindly, grandmotherly woman, to make a new life in this unforgiving rocky terrain. Their new guardian seems to be of their kin, and the caution and curiosity of her neighbours confirms to the alert Mara that she and Dann are in some way marked as notable, so special that many will come to seek them, many to suspect them, and disguise will often seem the best option. This new life is hard: hunger, dirt, thirst and danger are the children's constant companions as they grow into their selves. Drought and fire carry off their adoptive home and force them to set off northward into the unknown, to experience a series of adventures, cultures, trials, revelations and crises that bring them through to an altogether altered world, where they can start to learn and build anew, to achieve a new kind of notability.