Guards drag Jacin before the queen and charge him with treason for failing to capture Linh Cinder and protect Thaumaturge Sybil Mira. Jacin stays calm and claims that he was spying on Cinder while secretly serving the crown. He reveals that Cinder has a device that can block the Lunar gift, which helps his case.

The court presents a recovered message that supports his story, but Levana still doubts him. Winter watches in panic, thinking about whether she should intervene.

Levana spares Jacin’s life. Winter cries out in relief, drawing ridicule from the court. Levana sentences Jacin to 30 self-inflicted lashings and 40 hours of penance, then warns Winter not to help him.

Winter avoids seeing Jacin punished and spends the day quietly. That night, she feigns an emotional breakdown, crying out about a monster in her closet. While her guards search the room, she slips out of the palace and runs into the city.

She finds Jacin tied to a sundial on the public dais, wounded and exposed. They quickly fall back into their familiar rhythm. Jacin tells her about a device that can block the Lunar gift and says it might help with her hallucinations. He also admits that he joined Cinder’s group before betraying them.

Jacin reveals that Linh Cinder is Princess Selene, Winter’s cousin, and says Cinder is coming to Luna. He asks Winter to deliver a message to Scarlet before a guard interrupts them.

Cinder repairs the Rampion’s clogged oxygen filter while Emperor Kaito of the Eastern Commonwealth, known as Kai, watches her work. He kisses her, but Cinder cannot stop thinking about what will happen if they win. Even if Levana falls, Kai must rule Earth and Cinder must rule Luna.

Cinder also worries about her close friend Ze’ev Kesley, known as Wolf, a former Lunar special operative who is falling apart after Scarlet’s capture. Kai asks Cinder to practice her Lunar gift on him. She resists, then finally agrees and proves how easily she can control an Earthen by forcing him to perform simple movements.

Afterward, she reminds Kai that his most important job is convincing Levana to hold the royal wedding on Luna.

Scarlet Benoit remains imprisoned in Levana’s palace menagerie and passes time by throwing sticks to a captive white wolf named Ryu. Princess Winter visits with treats and tells Scarlet that Jacin returned and that all of Scarlet’s friends are alive. Scarlet finally breaks down and cries.

Winter hides a note inside a candy box for Scarlet, telling her that her friends are coming for her.

They talk about Cinder, Wolf, loyalty, and love. Scarlet insists that her bond with Wolf is only based on mutual need and survival. Winter does not believe her.

Crescent Moon Darnel, “Cress,”, a shy tech genius and shell previously imprisoned by Levana, briefs Wolf on the status of Scarlet’s farm back on Earth. Wolf, hollow with grief, asks her to search for information about his parents on Luna. He was taken from them at 12 and wonders whether they think he is dead. Cress cannot access Luna’s records from the ship, and Wolf shuts the subject down, insisting that Scarlet matters more. Cress makes him eat.

She then finds Carswell Thorne, a notorious thief and captain of the Rampion. His eyesight is slowly returning after weeks of treatment. He tells her he cannot wait to open his eyes and see her, then quickly adds that he wants to see everyone else too. Cress hides her disappointment and accepts that she loves someone who sees her as only a friend.

Jacin wakes in a suspended-animation tank with his lashing wounds healed. Aimery arrives to escort him through reinstatement and returns his weapons and uniform. Other guards openly treat him like a traitor.

Aimery hints that the queen has a specific role planned for him. As they travel up to meet Levana, Jacin forces himself to stay calm even though he dreads what is coming.

Levana restores Jacin as a royal guard and assigns him as Winter’s personal guard at Winter’s request. She orders him to keep Winter under control and hints that she has marriage plans for the princess. Jacin hides his reaction and accepts.

Winter waits for the guard change, thrilled when Jacin arrives. She shows him the model solar system she made to help steady herself during his absence. Jacin admires it but reminds her they cannot behave like friends while he is on duty. He admits that he cares for her more than he should, then retreats to the corridor. Winter joins him and paints beside him.

Cinder, Cress, Wolf, Kai, and Iko, an android and Cinder’s best friend, sort through the cargo bay, taking stock of their haul. Wolf picks up a gun like Scarlet’s, and grief nearly overwhelms him. Kai promises they will find her once they reach Artemisia.

Thorne appears without his blindfold, his eyesight fully restored. He looks at Cress, and she feels a surge of hope before pushing it away.

Kai wants to return to Earth immediately because his people are suffering. Wolf agrees, but Cinder insists they should wait until Levana weakens further. Kai keeps pressing until Cinder freezes at something on her retina display and announces that Kai’s palace is under attack.

The crew watches live coverage of an attack on New Beijing Palace. Lunar wolf soldiers launch a coordinated daytime assault, and the palace suffers major damage, though it still stands. The Commonwealth military fights them off but loses more than 300 soldiers.

A journalist reports that officials and servants have escaped safely. She also says that the Association for Commonwealth Security is calling for Kai to step down and that support for the idea is spreading online.

Cinder realizes they cannot delay any longer. She tells Thorne to prepare to take Kai home.

Cinder checks the podship before Kai leaves for Earth. Kai admits he is afraid but says he is ready to go home. He explains his plan: He will pretend Cinder and her crew held him hostage so Levana will not suspect their alliance.

Before leaving, Kai apologizes for how he treated Cinder at the ball and says he should have trusted her. They share a quiet kiss. Then the others arrive to say goodbye. Iko gives Kai a military medallion, and Wolf punches him in the face to help sell the hostage story.

Kai boards the podship, and Cinder watches him leave.

Kai rides to Earth with Thorne in the podship. They joke for a while, then talk seriously about Cinder and what her life might have been if she had grown up on Luna.

Kai surprises Thorne by promising to pardon his crimes if they both survive. In return, Thorne must give back everything he stole, including the Rampion. Thorne protests because the ship and crew matter too much to him.

Their conversation shifts to Cress. Kai realizes Thorne cares about her, but Thorne insists she deserves a better life than he can give.

Winter walks through Artemisia with Jacin while carrying embroidered gifts for workers and shopkeepers. She explains that embroidery helps keep her focused when her visions worsen. Winter reminisces about her mother and a treasured baby blanket, and Jacin tells her about seeing real snow on Earth.

Winter tells Jacin that his opinion matters more to her than anyone else’s. He admits that he cares about her but insists that nothing more can happen between them.

Children from a flower shop give Winter a handmade crown. She puts it on, but Jacin panics when he spots a security camera. He removes the crown and rushes her away.

Kai returns to Earth and contacts his advisor, Konn Torin, from a safe house. Palace guards and military officers bring him to an underground shelter where officials and staff take refuge from Levana’s attacks.

Kai tells Torin he plans to marry Levana to secure a cease-fire and gain access to the antidote to letumosis, an engineered plague that Levana uses as a biological weapon against the people of Earth. Torin warns him against it and reveals that Earth has been building bombs capable of destroying Luna’s biodomes. He also explains that letumosis was created in a Lunar lab and deliberately brought to Earth.

Kai states that the bombs should remain a last resort, but he hints that his true goal is to put a different queen on Luna’s throne.

Kai contacts Levana and pretends he still wants to marry her. He claims that Cinder and her crew abused him and pressured him to end the engagement. Levana mocks him, but Kai stays steady and says he still wants peace and the letumosis antidote.

He suggests moving the wedding to Luna because it would be safer there. Levana agrees at once and offers a cease-fire to any Earthen nations whose leaders attend.

She sets the wedding for November 8, only 10 days away, forcing Kai and Cinder’s allies to act quickly.

Cinder and the others listen to Kai’s audio feed as he finishes speaking with Levana. Thorne returns and gets angry when he sees that Cinder painted over the highly recognizable image on his ship.

He confirms that Kai reached Earth safely, the wedding is back on, and Levana has agreed to a temporary cease-fire. Cinder tells the crew to make their final preparations. She reminds them that they do not have to follow her into danger.

No one leaves. The whole crew commits to the plan.

Kai travels toward Luna and talks with Torin about Cinder. Torin points out that the public sees Cinder as a terrorist, though they view Princess Selene (Cinder’s alter ego) as Luna’s rightful heir. Kai believes in Cinder’s plan, though waiting is difficult.

Another ship hails them with a claim of technical trouble, and Kai already knows who it is. Cinder and the crew board disguised as American officials and guards. Their glamour (a form of magic that disguises their identities) fools the captain.

Kai leads them to a secure room, where Cress checks for surveillance. Once they are alone, everyone drops their disguises. Kai introduces Torin, Luna comes into view, and he gives the crew new clothes and supplies, including plating for Iko.

Winter lets a maid dress her for the arrival of the Earthen guests but refuses to hide her scars. After the maid leaves, she steps into the corridor and playfully tries to get Jacin to admit that she looks pretty.

She starts hallucinating. She sees blood on the walls and dripping from the chandelier. She calls for Jacin, and he calmly helps her through the vision until it fades.

Aimery appears and sends Jacin away. He tells Winter that he wants to marry her and that Levana approves. Winter stalls while Aimery mocks her and hints that he knows about her feelings for Jacin. When Jacin returns with a summons from the queen, Aimery grabs Winter and demands an answer. She refuses for now and leaves with Jacin.

Kai arrives on Luna with Torin and the other Earthen guests, trying to hide how nervous he is. Levana meets him at the royal port with guards, thaumaturges, and Winter. Winter startles him by joking that he is almost her father.

Levana orders her guards to search Kai’s ship. Kai panics because Cinder and the others are hidden aboard. When he objects, Levana reminds him that she does not trust him and warns that his stay will become unpleasant if he plans to betray her.

Cinder and her crew hide in a storage closet aboard Kai’s ship and plan to slip out through the royal port. When they hear guards searching the ship, Cinder uses her Lunar gift to shield Thorne and Wolf from manipulation.

Thorne volunteers to act as a decoy so the others can escape. While guards chase him, Cinder leads Wolf, Iko, and Cress through the ship and into the cargo bay, where they fight a thaumaturge and several guards.

They race for the maglev doors. Cress opens them from the control booth so the others can get through. Thorne makes it inside at the last second, but Cress is left behind. The others have no choice but to keep running.