Ember, built as a last refuge for the human race, is running out of power two hundred years later, but twelve-year-old Lina thinks there may yet be hope when she finds part of an ancient message that may hold a key to getting out of the city.
Lina and Doon are thrilled to see their people join them above ground in the vibrant village of Sparks, but suspicion and prejudice soon turn the villagers and newcomers against each other.
While visiting the small town of Yonwood, North Carolina, eleven-year-old Nickie makes some decisions about how to identify both good and evil when she witnesses the townspeople's reactions to the apocalyptic visions of one of their neighbors.
When a roamer trades them an ancient book with only a few pages remaining, Lina and Doon return to Ember to seek the machine the book seems to describe in hopes that it will get their new community, Sparks, through the winter.
