After the unicorn hunt, Elesbed hides behind a tapestry in Anne’s bedchamber and overhears the duchess and her lady-in-waiting, Hawiz, discussing the political value of the unicorn encounter. The tapestry moves near Elesbed, and she discovers a cat curling up beside her.

Elesbed falls asleep, but she’s woken by a hiss from the cat. She opens her eyes and sees the ghost of a woman whose throat has been cut, dragging a bloody sword behind her toward the duchess’s bed. Elesbed screams, throwing herself between the ghost and the duchess. When Hawiz and the other attendants rush into the room, the ghost disappears. Anne comforts Elesbed and asks her what she will name her cat. Elesbed chooses the name Butter.

The court returns to the castle at Nantes, where the man found in Brocéliande remains unconscious. Anne holds a council with Isabeau, Henri, Jean, and other members of her court. Isabeau, desperate to prevent Anne’s political marriage to the French, passionately suggests they seek magical aid from the korriganed, who may still inhabit the wood. When the council dismisses the idea, a distraught Isabeau flees the room.

Later, Elesbed finds a weeping Isabeau, who convinces her to visit the stranger, theorizing that korriganed show their true nature in the dark. They find his room guarded but hear a strange voice from within and see an unnatural light under the door. The man screams and falls silent. When the guard opens the door, they find him unconscious. Henri discovers the girls and brings them to Anne, who sees that Isabeau is wearing a kerchief that belonged to their deceased mother and was buried with her. Elesbed reiterates that according to folklore, when the Lost Lands are near, lost things reappear, while others are lost forever.

In Nantes, Anne makes Elesbed a part of her household as a companion for Isabeau. Her diviner, Calyx, reports that Marguerite of France is on her way to force the marriage negotiations, and Anne begins planning ways to delay her until Maximilien’s armies arrive.

Soon after, the stranger from Brocéliande awakens and is brought before Anne and her court. He introduces himself as Julien Moreau, a diviner who served King Philip the Fair under the name Miravi two centuries earlier before disappearing into the forest. Moreau claims to have no memory of his time in the Lost Lands except for a single message. Speaking in archaic Breton, he announces that the king of the korriganed wishes to marry the Duchess of Brittany and will send three signs to prove his power: water, fire, and memory. Having delivered his message, Moreau collapses.

Traveling with Marguerite of France, Louis of Orléans reflects on the terms of his freedom. When a messenger brings news of the korrigan-king rumor, Marguerite dismisses it but remains determined to secure the marriage between the duchess and her brother. As they approach Nantes, they are met by a chaotic welcome: Anne and her court are preparing a “Triumphal Entry” into the city to celebrate the unicorn hunt, complete with a massive wooden unicorn on a cart.

Anne greets them with a display of cheerful innocence, explaining the pageant. She wears a woven band of unicorn hair around her head. Marguerite is disoriented by Anne’s frivolous and headstrong persona, which clashes with the image of a pious maiden. Amused by the spectacle, Louis agrees to ride in the procession. When Louis mentions the korrigan-king rumor, Anne recounts Moreau’s message matter-of-factly and notes that because Moreau refused to renounce his claim, the Guild tested him and he passed. Determined to secure Anne for her brother, Marguerite instructs Louis to manage the situation.

During the Triumphal Entry into Nantes, Louis is struck by Anne’s beauty. Anne’s younger sister, Isabeau, confronts Louis, accusing him of betraying their family, but Anne intervenes, maintaining her guileless facade. The procession is interrupted when a parade float depicting the legendary drowned city of Keris begins to gush saltwater, sparking panic in the crowd.

To prevent a riot, Anne deliberately unseats herself from the wooden unicorn, forcing Louis to catch her and ride on his horse to the float. Standing amid the uncanny flow of water, she calms the crowd, and the flow ceases. The people cheer her bravery. Though shaken, Anne insists on proceeding to the cathedral for Mass to frame the miraculous event in a pious context. Afterward, Louis walks with her and questions her about what happened. She evades his inquiries and coolly rebuffs his familiar tone, reminding him of their formal stations.

On the castle battlements, Marguerite encounters Moreau, who says he came to watch for signs from the korriganed and expresses fear that he has brought danger upon the duchess. Meanwhile, Isabeau, convinced Moreau can help them, takes Elesbed to his unguarded room. She tells Moreau about the water sign and, in a moment of desperation, declares she will offer herself to the korrigan-king in her sister’s place.

Suddenly, the ghost of a strangled woman with a rope around her neck appears on the stairs. Moreau uses the reflection in his wine cup to banish the spirit. He tells a stunned Isabeau that he could do more if he had a proper mirror. Isabeau promises to find him one, and he swears he will help them. Elesbed is horrified by the bargain, but Isabeau orders her to secrecy, believing this sacrifice is her duty to Brittany.

In Flanders, Maximilien of Austria delays his voyage to Brittany after seeing what he believes to be the ghost of his late wife, Mary. Back in Nantes, Calyx informs Anne of Maximilien’s delay. At a banquet that evening, Marguerite pressures Anne to accept French protection, claiming she will tell King Charles that Anne’s status as a maiden is in question. Anne deflects, citing her unicorn-proven virtue.

Later, during a council meeting, a fiery apparition appears just as cries of “fire” echo through the castle. The court evacuates, but the fire turns out to be an illusion—the second promised sign. Marguerite again urges Anne to leave, but she refuses. That night, Moreau secretly visits Marguerite and admits the water and fire were minor tricks he managed without his mirror. He reveals he remembers his two centuries in the Lost Lands and has mastered the arts of enchantment and sorcery. He demonstrates by conjuring a weeping pregnant woman from a conjured coffer, and then drawing a real brooch from it, offering his power to France in exchange for status and influence. Marguerite accepts his allegiance.

Elesbed realizes Isabeau must have given Moreau the small, jewel-backed mirror Anne brought from Brocéliande. She resolves to warn the duchess, but she’s intercepted by Moreau, who claims he is the king of the korriganed and can travel through the shadows between the mortal world and the Lost Lands. To silence her, he traps Elesbed in an otherworldly castle. Her cat, Butter, appears beside her and leads her toward a potential escape route.

Meanwhile, Anne is troubled by a nightmare in which she is torn between her suitors. Feeling trapped and anxious, she decides to go riding at dawn to clear her head.

Anne’s riding party, which Louis joins, heads to a water-meadow outside Nantes. While riding, Louis advises Anne to negotiate with France for the future sovereignty of Brittany, to be inherited by her second son. Their conversation is interrupted when they discover a clearing laid out for a feast that is now spoiled and decaying. Anne notices the uncanny light, strange shadows, and ghostly figures, and is nearly drawn into a vision of a past picnic with her late father. Sensing the danger, Louis forcibly pulls her away, and the party retreats to the castle.

Returning to the castle, Anne retrospectively connects the day’s incidents to Moreau’s three promised signs—water, fire, and memory—and finds Isabeau distraught over Elesbed’s disappearance. She asks Calyx to perform a divination, but the attempt overwhelms him, and he collapses, warning of a korrigan curse. Isabeau confesses to giving Moreau the mirror. Just as Anne summons Moreau, a brief vision of a white-haired figure appears in the garden, followed by a monstrous sea-drake that lunges from an unnatural light.

Louis throws a spear, wounding the beast. Acting on instinct, Anne speaks to it in Breton, and it becomes calm. She removes the spear, and its silver blood splashes onto her, granting her the painful ability to perceive the multiple layers of reality. She commands the creature to leave, and it vanishes. Overwhelmed by her new sight, Anne faints into Louis’s arms. Witnessing this display of power, Marguerite conspires with the terrified Jean, who agrees to hand Anne over to the French to save her from the threat of the korrigan king.

Later, Marguerite returns to her chambers, alarmed to find a laughing and unchained Moreau. When Marguerite asks if he summoned the sea drake that imbued the duchess with power, he denies it, but confirms he can deliver Anne to her that same night.

Weakened by the sea-drake’s blood, Anne is taken to her chambers, her vision still fractured. She sees Elesbed’s cat, Butter, shrouded in a strange darkness she can now perceive. Within it, she spies Elesbed’s shadow and, using her new power, pulls the girl back from the Lost Lands. Elesbed reveals that Moreau trapped her and can travel through shadows at will. Anne orders Moreau’s death, but Louis arrives with grim news: Jean has betrayed them and is opening the castle gates to a waiting French company. Jean has also revealed Anne’s secret to Marguerite in the garden.

When Louis asks her what the secret is, Anne admits that she is married to Maximilien of Austria. Shocked, Louis grapples with the choice between betraying Anne and earning his freedom, or siding with Anne and betraying Maguerite. With the castle about to be taken, Louis inwardly curses his romantic feelings for Anne, and vows to help her escape.

The castle servants create a diversion by releasing horses into the courtyard, sowing chaos among the French soldiers. Meanwhile, the diviner Calyx, staggers into the room, sick and near death, to perform one last reading to determine Anne’s best escape route through the castle. With his dying breath, he tells Anne, “I see—there is a city in the sea. That is your salvation, Highness. A city in the sea” (182).

Anne’s group, including Isabeau and Elesbed, escapes into Nantes. Moreau attempts to stop them with magical obstacles—a crowd of ghostly figures in the cathedral square and a real wild boar. Anne uses her newfound powers to dispel the ghosts and find the boar’s layer of the world to send it away, but the effort drains her life force and causes her excruciating pain. They manage to flee the city, with the gravely weakened Anne riding on Louis’s horse.

During the flight from Nantes, Anne’s strength continues to fail. The group finds refuge at the castle of Châteaubriant, where Anne is taken to a bed, near death from the magical strain. She has a vision of the korrigan-queen, who reveals that the sea-drake’s blood is killing her and that only the unicorn can save her. The queen urges her to go outside.

Anne awakens and, despite the protests of those around her, insists on being taken out. Louis carries her into the courtyard. There, the unicorn appears and touches its horn to her, instantly healing her.

The next day, Anne and her escorts travel toward the city of Rennes. Louis announces he will ride to Ghent himself to hasten Maximilien’s arrival. Anne asks how she can repay him for giving up his freedom to save her. When Louis asks for a kiss, Anne feels surprised. She’s spent so much time thinking of herself as political currency, it’s a shock to remember that she’s a human being capable of desire. She realizes she wants Louis as he wants her.

When Anne hesitates, Louis nods respectfully and prepares to leave, but Anne stops him and they share a passionate kiss. As Anne and the others continue on their way, Louis rides east with handful of guards toward Ghent to speak to Maximilien on her behalf.