Torren watches hundreds of bedraggled Emberites crest a hill, and the people of Sparks walk out to meet them.

The town leaders of Sparks decide to let the Emberites stay for six months, housed in the Pioneer Hotel.

Tick Hassler openly heckles town leader Ben at the Pioneer Hotel, complaining loudly about the Emberites' living and eating conditions.

Lina visits Doon at the Pioneer Hotel but leaves feeling lonelier than before, finding him absorbed in Tick's social circle.

Caspar returns home with Maddy, and Lina overhears them planning to travel to a ruined city in search of treasure.

Lina secretly hides in Caspar's truck, determined to stow away on the journey to the ruined city.

Torren destroys two crates of tomatoes in a rage and falsely blames Doon, whose people are believed guilty without question.

The town leaders of Sparks hold a second meeting and ban Emberites from eating lunch alongside Sparks families.

Lina, Maddy, and Caspar arrive at the ruined city and find it far more devastated than any of them expected.

Lina and Maddy take Caspar's bikes and leave him behind in the ruined city, riding back toward Sparks.

Lina realizes while traveling with a roamer that the ancient songs describe the Emberites themselves as the buried treasure.

The town leaders of Sparks hold a third meeting and order the Emberites to leave the village immediately.

Doon watches Tick gleefully kill a baby bird during a war council meeting and walks away, deciding to command himself.

Ben fires the mounted pre-Disaster weapon at the crowd, but Mary deflects it skyward; it explodes and sets the plaza on fire.

The leaders of Sparks officially apologize and invite all Emberites to remain and join Sparks as equal members of one community.

Hundreds of Emberites emerge from their dying underground city and are reluctantly taken in by the small surface town of Sparks. The town leaders agree to house the Emberites for six months, but tensions rise as food grows scarce and cultural misunderstandings multiply. The troublemaker Tick Hassler stirs up resentment from within, while Lina embarks on a journey to the ruins of an ancient city in search of a better future for her people. Back in Sparks, events escalate until the town orders the Emberites to leave and a pre-Disaster weapon is brought out in a disastrous final confrontation. The weapon backfires and sets the plaza on fire, forcing both groups to cooperate to survive the blaze. In the aftermath, the leaders of Sparks officially apologize and invite the Emberites to remain as equal members of one unified community.

The headline events that drive Sparks and Ember from uneasy alliance to unified community.

Mrs. Murdo tells Lina that the mayor and his cronies drowned while secretly trying to escape from Ember.

Lina is frightened by Dr. Hester's hearth fire, and Torren explains the four wars and three plagues of the Disaster.

Doon's work group eats a tense lunch at the Parton family's house, and Doon bonds with young Kenny Parton.

Lina discovers an abandoned bicycle and teaches herself to ride it, feeling a brief rush of joy and freedom.

Doon shows Edward Pocket the chaotic stash of books in the Ark, and the elderly librarian throws himself into organizing them.

The Emberites raise a flag over the Pioneer Hotel, and the people of Sparks quietly raise a flag of their own.

Caspar refuses to share food with a starving roamer, who returns that night to steal provisions and dump dirt on the camp.

Maddy angrily tells Caspar that he turned the starving roamer into an enemy simply by treating him as one.

Tick, with a suspicious rash on his arm, urges Doon to seize the Sparks food storehouse by force.

Emberites awake to find poison oak dumped on the Pioneer steps, develop painful rashes, and erupt into a riot in the plaza.

Doon's father admits he does not know the right answer but warns Doon that violence only leads to more violence.

Torren climbs a pine tree beside the town hall to watch the final confrontation from what he thinks is a safe distance.

Doon climbs the burning tree and carries Torren to safety, even after recognizing him as the boy who caused so much trouble.

Kenny tells Doon he witnessed Tick gathering poison oak, exposing Tick as the one behind the sabotage against the Emberites.

Caspar returns with unused lightbulbs, and Doon builds a small electric generator with Lina's magnet and lights one of the bulbs.

Before arriving at Sparks, the Emberites learn that their old leaders drowned trying to escape, and Lina enters a world of fire and unfamiliar knowledge she must quickly learn to navigate. Meanwhile Doon builds new friendships and discovers a trove of books that give the Emberites' aging librarian a renewed sense of purpose. On the journey to the ruined city, Caspar's cruelty toward a starving roamer reveals how easily an enemy is made through indifference. Back in Sparks, Tick's hidden sabotage pushes the community to the brink of war, and Doon's father offers hard-won wisdom about the true cost of violence. The confrontation in the plaza leaves Torren trapped in a burning tree before Doon rushes to save him, after which hidden truths about Tick's treachery are finally exposed. The story closes with a small electric light flickering to life, suggesting that the Emberites' knowledge may help Sparks grow into something far greater.

The supporting moments and smaller stories behind the main conflict.

Walking to Dr. Hester's house, Lina is overcome by homesickness for a city she knows no longer exists.

Lina and Torren's breakfast argument escalates until Lina throws the only egg of the day at him, wasting precious food.

Tick befriends Doon while foraging berries, eats every one himself, and leaves behind handprints that look disturbingly like blood.

A spark from Caspar's campfire lands on Lina's ankle and burns her, deepening her long-standing fear of fire.

Kenny quietly reveals to Doon that the leaders of Sparks have knowingly set the Emberites up to fail from the start.

Anti-Ember graffiti reading 'they must go' is scrawled on the plaza cobblestones, marking the first open public act of hostility.

Tick wakes the entire Pioneer Hotel to show them 'go back to your cave' written in ash on the front wall.

Caspar explains to Lina and Maddy that careful study of different versions of ancient songs has led him to the treasure's location.

Maddy tells Lina that the only way to break the cycle of revenge is to respond to violence with kindness.

After a fountain confrontation, Doon realizes his angry reaction made him look exactly like the violent outsider Sparks believes him to be.

Camped near the ruined city, Lina feels homesick and realizes for the first time that she is thinking of Sparks, not Ember.

Lina returns to Sparks and reconciles with Doon, giving him a magnet and magnifying glass she collected while roaming.

Frozen by fear of the blaze, Lina forces herself to step forward and join the Sparks fire line, breaking the cycle of revenge.

While tending Torren's burned feet, Lina gently questions him and quietly realizes he lied about who destroyed the tomatoes.

Ben visits Torren to apologize for neglecting him, and Torren realizes for the first time that he is happy living with Dr. Hester.

From Lina's earliest homesickness at Dr. Hester's house to her explosive breakfast argument with Torren, the novel's turning points reveal characters discovering who they truly are and what they value. Tick's berry-stained handprints and his graffiti campaign are small but telling signs that he is engineering conflict from within, manipulating both communities toward war. On the road to the ruined city, a campfire spark injures Lina and deepens her fear, while Maddy's insight about breaking the cycle of revenge gives Lina the moral framework she will need at the story's climax. Doon's humiliating fountain confrontation forces him to see himself through Sparks' eyes, pushing him further from Tick's leadership and closer to his own values. At the climax, Lina overcomes her fear of fire and joins the Sparks fire line, an act that breaks the cycle of violence and inspires the other Emberites to follow. In the quiet moments afterward, buried truths about Torren's lie and Ben's neglect surface, showing that healing requires honesty as much as heroism.

The key decisions, discoveries, and emotional shifts that define both characters.