Chronologically third, but listed as fourth in the Book of Ember series, the latest entry begins with an enticing vision of pre-Disaster events, in which the Builders of the underground city make provisions to assist the emerging Emberites. Things are not going well in Sparks, as the stress of the Ember newcomers is bringing back a frightening scarcity of food, warmth and hope. This hard life pushes Doon and Lina into adventure as they discover an artifact that inspires them to return to their abandoned city to relieve their troubles. In so doing, the pair meets odd characters who add spice to events by managing to be humanely kind and selfishly scary in almost equal measure. Doon and Lina’s knowledge of Ember helps them find solutions in dire straits, but it also takes work and grit to discover the true meaning of the jewel-like object central to the plot. Readers will find this fast-paced and clever final installment closer to the original than either of the other sequels and will enjoy the logical future detailed at the end. (Science fiction. 8-12)
