Prince Kai arrives in disguise at Cinder's market booth, asking her to repair his broken android.

Letumosis spots appear on Peony's collarbone at the junkyard, and med-droids take her to quarantine.

Adri blames Cinder for Peony's illness and volunteers her for the letumosis cyborg draft.

Cinder wakes up restrained on a lab table with her synthetic parts exposed and wired to machines.

The research team injects Cinder with letumosis without her consent to test her reaction.

The letumosis microbes injected into Cinder's bloodstream vanish before the research team's eyes.

Dr. Erland tells Cinder she survived the letumosis injection without any antidote, confirming her immunity.

Emperor Rikan dies of letumosis, and Torin informs Prince Kai that he must prepare to rule.

Queen Levana arrives in New Beijing with Sybil Mira immediately after Emperor Rikan's death.

Cinder visits Peony in the quarantine ward; Peony says she loves Cinder and wants to go home.

Queen Levana presents Kai with a letumosis antidote as a coronation gift, demanding marriage as the price.

Cinder rushes to the quarantine with the antidote, only to find Peony has already died.

Cinder drives the gasoline car to the ball in the rain, crashes into a tree, and arrives soaking wet.

Cinder dances with Kai at the ball and reveals that Queen Levana plans to have him killed.

Queen Levana exposes Cinder as Lunar at the ball; Kai rejects Cinder and agrees to have her imprisoned.

Cinder, a cyborg mechanic in futuristic New Beijing, meets Prince Kai at the market and is soon after dragged into letumosis plague research by her resentful stepmother. After surviving an unauthorized injection of the plague, Cinder discovers she is immune and becomes the key to finding a cure, negotiating her participation in hopes of saving her stepsister Peony. The political landscape darkens when Emperor Rikan dies and Queen Levana arrives demanding marriage to the new emperor in exchange for a plague antidote. Cinder narrowly misses saving Peony with the antidote and is left with nothing but a plan to escape the city. On the night of the coronation ball, a critical warning forces her to abandon escape and rush to Kai instead, arriving in the rain, disheveled and desperate. Her act of bravery ends in catastrophe when Queen Levana exposes her as Lunar, Kai rejects her, and Cinder is taken away to a prison cell.

The central story of Cinder's discovery, sacrifice, and the ball.

Chang Sacha the baker collapses with letumosis at the market, triggering an emergency evacuation.

Cinder returns home to Adri overseeing dress fittings; Adri lies about allowing Cinder to attend the ball.

Cinder, Iko, and Peony discover an old gasoline-powered car at the junkyard and Cinder imagines it as an escape vehicle.

Adri is shocked and furious when Cinder returns home from the research lab still alive.

Cinder tells Iko about her research experience and decides to use the payment to fix the gasoline car for escape.

Prince Kai visits his quarantined father Emperor Rikan through a window and hears Rikan tell him to be strong.

Sybil Mira confronts Prince Kai at the palace to press him about forming a Lunar alliance.

Kai confides to Torin his plan to find the missing Princess Selene as an alternative to marrying Queen Levana.

Cinder and Prince Kai share an elevator ride at the palace; Kai tells her Emperor Rikan has died.

Kai invites Cinder to attend the ball during their elevator ride; she declines because she is a cyborg.

Adri demands Cinder's mechanical foot as payment for Peony's memorial plaque, blaming Cinder for Peony's death.

Cinder discovers that Adri has dismantled Iko, leaving only the android's personality chip behind.

Kai visits Cinder at her market booth on the day of the ball and leaves her a gift of white gloves.

Adri confronts Cinder on the ball's grand staircase; Kai intervenes and leads Cinder onto the dance floor.

Dr. Erland uses his Lunar magic to bypass palace guards and speak privately with the imprisoned Cinder.

From the plague outbreak that disrupts the weekly market to the dress fittings that highlight Cinder's second-class status at home, these events establish the social landscape she must navigate every day. The discovery of an old gasoline car at the junkyard sparks Cinder's dream of escape, while her growing interactions with Prince Kai — from a shared elevator ride to a final gift of white gloves at the market — reveal a bond complicated by class and hidden identity. The dying emperor's final words to Kai, Sybil's political pressure at the palace, and Kai's secret plan to locate Princess Selene each raise the stakes of the Lunar threat looming over the Commonwealth. Adri's cruelty reaches its peak with Iko's dismantling and the theft of Cinder's prosthetic foot, stripping away everything Cinder has worked for. At the ball, Adri attempts one final act of humiliation before Kai steps in to defend Cinder. Even in imprisonment, Cinder receives a pivotal private visit that will change the direction of her life.

The supporting events that build Cinder's world and relationships.

Med-droids test Cinder's blood after Peony is quarantined and confirm she carries no letumosis pathogens.

Cinder negotiates with Dr. Erland to receive private payment and secure Peony as the second antidote recipient.

Dr. Erland presses a spot on Cinder's neck during an examination, causing her to collapse in sudden pain.

Prince Kai sees a holograph of Cinder's extensive synthetic body parts displayed on a screen and recoils in disgust.

Dr. Erland warns Cinder to flee the palace before the queen's arrival and reveals she is a Lunar shell.

Queen Levana's glamour briefly makes Kai believe he loves her before he shakes free of the mental manipulation.

Cinder discovers an unauthorized thirteenth D-COMM chip hidden inside Prince Kai's android Nainsi.

Nainsi powers on and transmits classified information about Princess Selene, revealing a Lunar spy operation inside the palace.

Cinder defies Dr. Erland's warnings and returns to the palace to deliver Nainsi and her findings directly to Kai.

Queen Levana tells Kai he is harboring a Lunar fugitive on Earth, unaware that the fugitive is Cinder.

Dr. Erland reveals that a chip on Cinder's spine, invented by her adoptive father Garan, has been suppressing her Lunar abilities.

Dr. Erland accidentally reveals that he himself is secretly a Lunar living illegally on Earth.

A Lunar girl contacts Cinder through the D-COMM chip and warns that Queen Levana intends to kill Kai after their wedding.

Cinder kisses Kai to stop the marriage announcement; Queen Levana retaliates by forcing Cinder to hold a gun to her own head.

Dr. Erland reveals to the imprisoned Cinder that she is the missing Princess Selene, heir to the Lunar throne.

Cinder's story turns on a series of revelations that unravel the truth of her identity piece by piece. From the blood test confirming she carries no plague to her bold negotiation for agency within the research program, Cinder begins to assert herself in a world that treats her as property. Dr. Erland's hidden experiment triggers a mysterious pain that hints at a suppressed power, while a spy chip found inside Prince Kai's android exposes a Lunar intelligence operation reaching deep into the palace. The queen's glamour unexpectedly affecting Cinder, Erland's slip about his own Lunar identity, and the discovery that Garan's spine chip has been locking away her abilities each crack open new dimensions of who she truly is. A desperate warning from a Lunar informant forces Cinder to abandon her escape and confront the queen directly at the ball, where she kisses Kai, rejects the queen's mental manipulation, and fires a weapon before fleeing. In the aftermath, stripped of all pretense and imprisoned, Cinder receives the revelation that changes everything: she is Princess Selene, heir to the Lunar throne.