Days into the journey, Caspia abandons the stifling carriage at a rest stop. Andreas has organized fifty soldiers, supply wagons, a healer, and the guidance of Seth Hay, a merchant whose family specializes in traversing the Evon Ravine. He persuades Caspia to endure the carriage through lionwick territory.

Almost immediately, a soldier is killed, and a bloodied horse bolts past. Two lionwicks attack. Andreas shoots the first with a crossbow bolt; the barbed tail of the second slashes his chest when the couple shove each other clear. Caspia grabs his sword and decapitates the creature. The healer confirms that the wounds are not life-threatening.

Surveying the dead predators, Caspia reflects on killing for the first time and wonders whether the Starling bond with beasts still holds in Calandra, and whether destroying the orbits might make its monsters less savage. When a soldier offers to clean the blood from her hands, she refuses, keeping it as a reminder of everything at stake.

Ransom explains that the Kennin are an exiled Voster faction who believe magic-users should govern the kingdoms. If the High Priest discovers Dime’s dual loyalty, Ransom warns, the fallout could destroy Odessa’s father. This prompts Odessa to confess what she has withheld: Luella’s journal, Dime’s warnings, the waterfall caves, and her dealings with Skore. Ransom later arranges for a sealed letter to reach the High Priest through a ranger in Perris.

A note from Mae draws Odessa to the gardens with Faze. Nine drunken guards ambush her to steal Faze for profit. Mae arrives and attacks one; the sisters fight back but are badly outnumbered. A guard holds a knife to Odessa’s throat while another assaults Mae. Faze distracts the captor long enough for Odessa to seize his blade and kill him. Ransom then arrives and cuts through the remaining attackers, continuing to beat the last one to death well after he stops moving. He turns on Odessa with silver eyes before horror overtakes him and he disappears into the night. Mae watches and asks whether Ransom is truly not a monster. Odessa can no longer answer with certainty.

The expedition descends the obsidian Evon Ravine in near silence. Seth Hay leads the group; several soldiers suffering vertigo are sent back. At the ravine floor, Caspia immediately feels a sharp pain she recognizes as coming from the magic emanating from an orbit, and she follows the sensation deeper into the chasm.

The group hears shrill chirps just before Seth Hay’s body drops dead beside them, his throat slashed. A chiroptus—a massive, four-winged, blood-drinking bat that hunts by sound—swoops at the group. Andreas orders everyone against the wall and commands them to conceal their flames. The soldiers watch helplessly as the creature feeds on Seth’s body before Andreas wounds it and orders them to open fire. They bring it down, but a soldier who steps forward to confirm the kill is immediately taken by a second chiroptus. The soldiers destroy that one too.

Caspia presses on through mounting pain until she reaches an apparent dead end, detects a hidden tunnel, and pushes through. The agony intensifies so severely on the other side that she vomits. Tracking the sound of running water, she finds a colorless waterfall with an orbit resting in its pool. Andreas stops her from touching the water and retrieves the orbit himself—a glass sphere containing a swirling magical tempest. Caspia loses consciousness as relief washes over her.

Ransom does not return to the suite after the attack. The next morning, Alore reports no progress on the Lyssa cure. In the castle foyer, Odessa finds five arrivals: Samuel Hay, a journalist; his son Jonas; the healer Geezala; Cathlin; and Zavier, who is gravely ill. Evie and Zavier have a tearful reunion.

Mae then bursts in with word that King Cross has arrested Ransom. Odessa stops Zavier from intervening and announces that they must leave for Turan. Mae insists on coming, revealing that King Cross is not her biological father. Odessa assures her that they will always be sisters.

Confronting her father in the throne room, Odessa reveals her knife wound and claims she killed the guard who held her. Her father declares Ransom exiled and orders her to remain; she refuses both conditions. Her accusation that he orchestrated the confrontation with Ransom makes him pale, suggesting he had no part in the garden ambush.

At the barracks, Odessa bribes her way to Ransom’s cell. He is silver-eyed and trembling with rage, urging her to leave. She stays. When Brother Skore appears in the corridor, Odessa begs him to help, and Skore begins siphoning the Lyssa from Ransom’s blood.

A vision shows four Voster entering a sunlit throne room, deflecting Andreas’s thrown dagger with magic before scattering to hunt a crying baby. They cannot be stopped.

Back in Roslo, Andreas confirms that the orbit is locked in his family’s vault. The magical pressure immediately lifts, and Caspia suspects that her Starling senses have slightly weakened since the orbit was removed from the water. Half of the men left behind with the horses were killed by the chiropti; Caspia has no memory of leaving, as Andreas carried her out unconscious.

Caspia agrees they should lie low. Andreas plans to bring the soldier Taven and Faxon into their confidence and quietly work toward locating the remaining orbits, holding off retrieval until they know how to destroy them. He confides that the truth about the Six has shattered his lifelong faith; Caspia promises to teach him about the Divine. He rests his hands on her pregnant belly, and the baby kicks.

Skore’s intervention has purged the Lyssa from Ransom’s blood and broken his fever. Ransom is grateful but unsettled by the priest’s power.

Ransom then discloses a secret he has been keeping since before leaving Ellder: The crux he killed shifted into the body of a red-haired woman after it died. He believes she was a shapeshifter and not a migration scout, and he notes that her hair was the same shade as Odessa’s. Odessa concludes that the creature was hunting her, and she’s devastated to think she may have caused Luella’s death by inadvertently drawing the monster to Ellder. Ransom firmly denies it. He had the green-blooded body burned before his father, King Ramsey, could see it. Ramsey rode to Allesaria without ever learning the truth and has not warned the other kingdoms.

Queen Margot arrives and dismisses the guard. Unable to free Ransom because King Cross holds the cell key himself, she produces a dark purple book. She explains that she always acted to honor a vow of protection, and that Odessa’s elfalter necklace called to her exactly as Caspia predicted. She tells them to read the book together and says Odessa’s father will be waiting on the throne room balcony when they are finished. She describes the book as their dynasty.

A past vision shows Emery arguing with her Aunt Oleana in the Showe castle mews. Oleana forbids her from sailing to Calandra, warning that Caspia’s visions foretold her death there. Emery recounts years of Beesan captivity: her blood used for experiments, her child and her companion Max held hostage to control her. She refuses to abandon her sisters. Once Oleana leaves, Emery fixes her gaze on the horizon.

In the present, three months after giving birth, Caspia sits at her vanity while Andreas—now King of Quentis—rocks their daughter. He proposes naming the baby Dess, after Caspia’s mother, Odessa.

A steward announces four Voster in the throne room. Caspia recognizes the moment from her vision. After Andreas departs, she hides her elfalter necklace in a secret floor compartment, hands baby Odessa to Margot, extracts a vow of protection, and leaves the journal for Margot to pass on when the time comes. Knowing that Margot loves Andreas, she instructs her to care for him after she is gone. Then she walks to the throne room.

Events unfold exactly as foreseen. The Voster repel Andreas with magic. Baby Odessa’s cry draws the priests toward the nursery. Knowing the Voster will kill them all, Caspia tells Andreas to drive his sword into her heart without hesitation—and surrenders to the shift, becoming her full Starling form and killing the Voster in the process.

Inside the Starling form, Caspia struggles against the monster’s urge to kill. Andreas drops his sword and tells her he loves her. Baby Odessa’s distant cry gives Caspia a brief moment of control. She holds the bloodlust in check long enough for Andreas to reclaim his sword and do what must be done. She is called home to the Divine.

Two days after Caspia’s death, Taven finds Andreas on the throne room floor, cradling her lifeless body. Taven returns with the nursemaid Nathalia and baby Odessa. The baby looks exactly like Caspia, which shatters Andreas further. Seeing his wife’s green blood on his own hands, he recoils and orders them both away, consumed by self-blame. When Taven begs him to release Caspia, Andreas collapses, sobbing, and refuses.

On the throne room balcony, Odessa confronts her father after reading Caspia’s journal. He admits killing her mother and says he has hated himself for it every day since, adding that he kept the truth from Odessa because he feared she would take up Caspia’s fight and sacrifice herself the same way.

They reconcile and talk through the night. He recounts how Caspia killed the four Voster priests before the bloodlust took hold, then asked him to end it rather than risk harming anyone else. He held her body for two days before General Hawksley—a longtime Kennin ally—took her away. The Voster bodies were burned, and Hain was set up as a scapegoat to deceive the High Priest. The Kennin’s true aim, he explains, is to destroy the orbits and break the ancient blood oaths binding them to Calandra, freeing them to return to their homeland, Kenn. One orbit is in the castle vaults; a second is beneath the crypts; a third likely sits under the Voster sanctuary in Allesaria. No one yet knows how to destroy them. He also reveals that neither Mae nor her brother Arthy are his biological children, and that Caspia was the last person he loved. He gives Odessa ten elfalter rings and the key to Ransom’s cell.

Odessa slips out early and leaves a saliva sample for Alore to test against the Lyssa elixir. In the foyer she finds Thora and Jodhi, the Mavins, rehired by her father in exchange for a chance to deal with Salem and tasked with keeping Odessa alive.

In the library, the head librarian Faxon mistakes Odessa for her mother. His son Kos escorts her to Caspia’s old reading carrel and produces a green leather journal Caspia hid in the stacks with a note instructing Kos to give it to her daughter someday. The journal contains more of Caspia’s visions.

Brother Skore joins her and reveals that he knew Caspia when he still wore the Voster’s red robes, under the name Brother Nold. He explains that magic is poison to the Starling bloodline, and that Odessa’s Calandran birth and mixed parentage make her more like the ancient Starling than her Nelfinex relatives. Monsters are drawn to her because of the Starling bond with beasts. Lyssa will eventually kill Ransom but will not cause him to shift. Odessa theorizes that Ransom was bitten by Xandra in her bariwolf form and that Starling saliva combined with Luella’s elixir created Lyssa. Skore says destroying the orbits may weaken Lyssa but is not a certain cure. He closes by telling her that the warrior she was always meant to find is herself.

At a clifftop above the sea, Ransom embraces Odessa from behind. She tells him the Mavins are back, hired by her father. They vow to face the future together, and Ransom tells her he loves her, using her full name. She replies that she knows and tells him not to forget.

As he pulls her from the edge, Odessa briefly feels a thrumming pulse in her chest—echoing the sensation described in Caspia’s visions—and lies, telling him it is nothing.

The novel ends on a final vision: A silver-eyed warrior, implied to be Ransom, kneels bleeding green as a massive, winged creature descends on him. Before he meets his end, he whispers a final tribute to his queen.