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This article contains plot details about an upcoming episode.
He is a Legend
She is a Prodigy
Who will be Champion?
June and Day have sacrificed so much for the people of the Republic—and each other—and now their country is on the brink of a new existence.
June is back in the good graces of the Republic, working within the government’s elite circles as Princeps Elect while Day has been assigned a high level military position.
But neither could have predicted the circumstances that will reunite them once again. Just when a peace treaty is imminent, a plague outbreak causes panic in the Colonies, and war threatens the Republic’s border cities. This new strain of plague is deadlier than ever, and June is the only one who knows the key to her country’s defense. But saving the lives of thousands will mean asking the one she loves to give up everything he has. With heart-pounding action and suspense, Marie Lu’s bestselling trilogy draws to a stunning conclusion.
The story starts out in the Republic of America, with Day living with Eden and Eden's caretaker, Lucy. Day's health is deteriorating, now having to resort to new medications while still battling the constant headaches and spasms.
In the beginning of the book, Day heads out by himself into the city and enters a pub and dances with a cute girl that reminds him of June, who he hasn't seen for months. For security reasons, he is also fitted with an earpiece from the government of the Republic. While he is inside the pub, he gets a call from a captain regarding June, inviting him to this banquet in which the elite circle of government officials, senators, and the Elector will be attending. Day has no choice but to accept the offer although he wants to disassociate with June so she won't have to feel the pain of his inevitable death from a brain injury.
Meanwhile, June is witnessing the trials of Commander Jameson and Thomas Bryant. Commander Jameson is warning them at the trial while Thomas attempts to act as the too loyal soldier that he is. Both are convicted guilty and sentenced to death by firing squad.
June also mentions to Day that there is a plague in the Colonies that the Colonies blame the Republic for as they used some biological weapons in the war between the two. However, June does not mention that Eden, who was experimented on as a biological weapon by the republic before he was set free, is the suspected culprit of this plague and only if Day will offer Eden up for life risking tests, the republic has no chance of finding a cure and no chance of defeating the colonies as the Colonies allied with one of the world's major military superpowers, Africa.
At the banquet, Anden, the Elector of the Republic reveals the true reason to bring him here and pleads with Day to allow tests to be conducted on Eden. Day refuses as he is afraid that he will lose his brother again to the republic in a test that his decisions could have averted.
Day has a excruciating headache and is immediately rushed to the hospital for treatment where a doctor gives him the diagnosis that he has about two months to live. Anden is informed of the bad news and relays it to June, who quickly goes to have dinner with Day. Day tells her the magnitude of his brain injury when an alarm goes off. The Republic has been invaded.
June and Day evacuate with the rest of the Denver citizens. As they reach the underground bunker, Day is infuriated that only the rich people receive shelter in the bunker while poor people are left to fend for themselves. he also realizes that some former Patriots, namely Tess and Pascao, are being held captive in the bunker for allegedly attacking a military base. Day leads them on a strike at the Colonies' air base after informing Eden about the testing that has to be done on him to save the country. surprisingly, Eden agrees to the testing.
June and Anden head to Ross City, Antarctica, to beg for help from the best military nation in the world. Antarctica has cutting edge technology and a system of "Points" that control the status of all life so that life in Antarctica is like a game with real consequences or rewards. Antarctica is only funding cure research because of their long rivalry with Africa. Because of the plague, all borders, airports, and ports are closed, quarantining the entire continent. June also learns a bit about the business oriented colonies and the history of North America. As June and Anden return to the Republic, they receive the grim news that Denver, the capital, has fallen to the Colonies.
In the meantime, Day is destroying Colonies jets outside of Denver in an effort to help protect the city. Before Colonies soldiers can kill him, Thomas comes to his rescue and shoots at them, but is killed in the process. Day ends up on the last train out of Denver, fleeing just as the escape tunnel is induced to collapse.
Back in the hospital again, after a severe headache was triggered by an explosion (to collapse the Denver to Los Angeles escape tunnel), Day is contacted by the Chancellor of the Colonies. He is blackmailed, under the threat that if he doesn't tell the people to revolt against the Republic, June and Eden will die. If Day does agree, he is promised access to medical care and protection. The Chancellor gives Day a three-day ceasefire to make up his mind. Right after the call ends, Tess is put into quarantine because she has become infected by the plague running rampant in the Colonies.
On the first night of the ceasefire, June and Day are reunited. They profess their love for each other and have a bed affair.
In the middle of the night, Day wakes up from a nightmare. He leaves June's apartment to visit his old home in the Lake sector, not knowing that June followed him. There, he reminisces what happened to his family. Then he breaks down in tears, because he doesn't want to feel the pain of losing his family, which June had been involved in.
On the second day of the ceasefire, Eden is admitted to the hospital for testing. After the testing is done, Day gets a call about June - she's been attacked by Commander Jameson, who is feeding the Colonies information about the military strengths and weaknesses of Los Angeles. Knowing the need to buy time, Day convinces Anden and June to pretend to surrender - who in turn convince the Senate. After the Senate meeting, Anden tells June he gave up Dakota, the Republic's largest territory, in exchange for military support (and treatment for Day) from Antarctica.
At the same time, Day plans to use the people to help fight against the Colonies and puts out a message across LA using spray paint - "LISTEN FOR ME." When he gets back, the lab technicians tell him that Eden cannot provide a cure for the plague, because the virus is a mutated version of the one Eden was infected with.
Anden officially announces the Republic's surrender when enemy airships begin to approach LA in anticipation of the end of the three-day ceasefire. During the announcement, June heads to the hospital to check on the cure progress. When the lab tech explains why the cure isn't working, and where it originated, June realizes that the infection she caught (in Prodigy) might be the same disease as the plague. While June goes to be tested, Day heads out to sabotage the landing bases being used by the Colonies to dock their ships.
Once the mission is complete, he receives a call from the Chancellor telling him that the speech to make the people revolt must be given on board one of the Colonies airships.
The results come back from June's testing - she isn't the origin of the virus, but she's close enough. June calls Day on her earpiece, but the frequencies are being jammed by the Colonies. The hospital is attacked, and soldiers begin to search for Eden. June attempts to defend him, but is knocked down by the soldiers. Before the last one can strike and knock her unconscious, Tess attacks him. The cure engineered using June had worked well enough for her to recover in a short span of time.
By this time, Day is on board giving his speech to the citizens of the Republic. At the last possible moment, he tells the people to revolt against the Colonies instead of the Republic, then flees. On cue, the bombs attached to the bases explode. This provokes the Colonies to action, and fighting begins in LA. June opts to fight instead of escaping to safety, and leaves Eden with a nurse. June disables several soldiers and then discovers one of them is Commander Jameson. Jameson is attempting to kill Day, but June attacks her. June, with the help of soldiers on the ground, kills Jameson.
When June rushes down to see Day, she finds that he is fatally injured. Day is soon taken to the hospital, where the doctors stitch up his wounds. Day would have died from the infection in his hippocampus, so the doctors also perform surgery on his brain.
Antarctica saves the Republic, and Day remains in a coma-like state for five months. When he wakes up, he has retrograde amnesia. He roughly remembers the happenings of the last year he spent with June; only remembering major details, such as his mother's death and how Eden was sick and managed to survive. The sad and terrible truth that he forgets who June is. June thinks the situation over and decides that she will not remind him of who she is and leaves after visiting him and acting as a stranger. After Day recovers, Eden is offered a place in one of Antarctica's engineering schools, in which Eden accepts and they both leave the Republic. This leaves June to reminisce about her time with Day and how she'll never forget him.
Ten years later, Eden and Day return to the Republic so that Eden can be interviewed for an engineering job in LA. It just so happens that to be June's birthday, and she is on her way to dinner, when she gets a message from Tess telling her that Day and Eden are in town. Almost to her destination, she runs into Day and Eden. Day stops and recognizes June, (not completely though). He stops June after catching a glimpse at her asking if he knows her. Convinced he's seen her before, he decides to start over and introduces himself saying, "Hi, I'm Daniel." June responds, "Hi, I'm June."