Sequel to: The City of Ember.

Arrival -- What Torren saw -- Out from below -- Through the village -- The doctor's house -- The first town meeting -- The pioneer -- Breakfast with disaster -- A day of new people -- The roamer and the bike -- Hard, hungry work -- Restless weeks -- Tick's projects -- Caspar arrives with a surprise -- Taking action -- Travelers and warriors -- What Torren did -- A long, hot ride -- The starving roamer -- Doon accused -- The second town meeting -- Caspar's quest -- Unfairness, and what to do about it -- The city destroyed -- Attack and counterattack -- Discoveries -- The third town meeting -- Getting ready for war -- The decision -- What Torren planned -- Dread at the last minute -- The weapon -- Firefight -- Surprising truths -- The fourth town meeting -- Three amazing visits.

Having escaped to the Unknown Regions, Lina and the others seek help from the village people of Sparks.