Day and June, Legend’s two main protagonists, are an unlikely pair. Day is a scruffy criminal on the run from the law, and June is the Republic’s star citizen. June is the only known person to have scored a perfect score on the Republic’s Trial, a rigorous exam given to all ten-year-olds to determine their future. Day hates the Republic for all the injustices it has committed against his family and other members of the poor sector he grew up in. His conflict with the Republic is the main conflict of the novel. June, on the other hand, pledges her allegiance to the Republic every day and dreams of being the one to capture its most wanted criminal, Day. As a loyal member of the Republic, then, June personifies the conflict with Day at the beginning of the novel. These two characters also provide the first-person narration of the novel, as it is told in alternating chapters titled “Day” and “June.”

Things get complicated when June’s brother, Metias, is murdered during a break-in at a local hospital that Day stages to steal a plague cure for his family. The murder is the inciting incident of the plot. June assumes Day murdered her brother and is encouraged when Commander Jameson, the Republic’s military leader and one of the novel’s main antagonists, moves up June’s graduation and puts her on the case. June goes undercover to hunt for Day and successfully locates him in the Lake sector. The problem for June is that Day turns out to be much kinder and more considerate than she expected. She also has had a nagging doubt that Day is her brother’s killer because Day never murders his victims, only harms them. To complicate matters more, June and Day have become attracted to each other, not only because they’re both beautiful but also because they are equals, mentally and physically. All these emotions set up an internal conflict in June.

Despite her misgivings, June resolves to turn in her brother’s killer, or so she tells herself, so she stages Day’s capture at his family’s home. When Day is cornered, he stubbornly refuses to give in, prompting Commander Jameson to order his mother’s execution on the spot in retaliation. From this point on, June’s faith in the Republic is severely shaken. She’s no longer convinced of the noble mission of the Republic, nor its values. Meanwhile, Day, extremely distraught, is captured alongside his brothers John and Eden. Day and John are imprisoned, while Eden, who has the plague that is running rampant through the poor sectors, is taken away by generals. Day, like June, is forced to question his actions. Rebellious from day one, Day wonders if he has gone too far and is now wracked with guilt over his mother’s death. 

Day is sentenced to execution, and June is put in charge of interrogating and guarding him. During these chapters, June realizes that Day is telling the truth. He did not kill Metias, and the Republic is far more sinister than June ever would have believed. June discovers through her brother’s journals that the Republic had their parents murdered and that kids that fail the Trial aren’t sent to labor camps, as the Republic maintains—they’re killed. June also learns to her horror that the Republic deliberately infects the poor sectors to test out new strains of the virus to use against the rebel Colonists. June’s faith in logic, order, and society is now completely undone. Day, for his part, has learned that not all government officials are evil and that they may be subject to the same abuses poor people are. June’s family has been destroyed by the Republic too. 

June decides to save Day and bring him to freedom. Her plan goes awry, however, when Commander Jameson pushes Day’s execution up one day because she is annoyed that a large group of protesters has gathered on Day’s behalf. The climax of the novel occurs when June and Day escape the Republic, but only because Day’s brother John willingly gives up his life for them. John switches places with Day and is executed, a final sobering reminder that freedom comes at a cost. The falling action of the novel begins when June and Day make their way to the outskirts of town to collect themselves and plan their next move. The novel’s resolution comes when Day, true to his family above all else, resolves to save his brother Eden, and June, who realizes that Day is now her only family, decides to fight beside him as his trusted ally. Both characters learn that their government has propagated an artificial enmity between the poor and wealthy. Day and June are two sides of the same coin, and they put their prejudices behind them for good.