That same night, Agnes returns alone to Havelock’s workshop to search for Vortigern’s book. She is briefly interrupted by His Majesty, who has found his own way in and is attempting to eat one of the luminous spiders. 

Agnes descends through the progressively more chaotic lower floors, which are crammed with boxes and crates. Behind the staircase connecting floors three and four, she finds the trapdoor Yannick mentioned. Contrary to Yannick’s warning, it is not locked. Agnes lifts it easily and descends into a small, cozy room revealed to be Havelock’s private living quarters. There, she is startled to find Havelock slumped asleep on a couch, clearly wounded.

Agnes sees that Havelock’s left leg has a deep gash and is also flickering with a dark spectral form. She wakes him; fearing the worst when he shuts the trapdoor with a spell, she is relieved to learn he closed it only to keep His Majesty out. 

As Agnes bandages Havelock’s wound, she confesses she was looking for Vortigern’s book to give to Valérie. Havelock explains that he was injured by a specter in the Rivenwood and that magicians who spend too much time there risk losing their human form and becoming one. He also reveals that one of his eyes is a different color because a beauty spell he cast on himself is malfunctioning.

He then tells her the real reason Valérie found him: She cast a tracking spell months ago that accidentally attached itself to Agnes’s cats. Agnes realizes this errant magic is why she was compelled to visit Rue des Hirondelles. Havelock confirms Valérie believes Vortigern’s book is part of a collection he acquired from a deceased magician named Walker Clem, but he insists the book was not among the Artefacts. Agnes suggests it could be disguised by an illusion and proposes to organize his chaotic collection to find it. Havelock pushes back, but Agnes presses him and he concedes. She leaves with the agreement in place.

Agnes’s plan to organize the workshop is delayed by morning events at the shelter. A cat named Thoreau has fallen ill, and someone has abandoned three new kittens on their doorstep. A veterinarian, Dr. Noémie Para, visits and determines Thoreau is merely experiencing stress due to the shelter’s recent magical relocation. Soon after, a local baker named Rémy arrives to adopt a cat named Biscuit for his husband, Oliver. Rémy informs Agnes that a rumor is spreading about the shelter selling enchanted cats, traced to a recent customer who claims his new cat cured his insomnia. Rémy also reports that three of Valérie’s followers started a major fire at a local café, Miette, while showing off. The news of both the rumor and the ongoing danger from Valérie’s apprentices inspires a new plan in Agnes’s mind.

Élise arrives, furious about having to retain their second location at Rue Sainte-Sophie. She complains the excessive opulence of the new shelter, which was formerly a jeweler’s shop. After Agnes recounts her discovery of the wounded Havelock, Élise accuses her of treating the magician like another stray cat she needs to fix. 

Just then, Havelock is found sitting on the counter in the shelter, having come up from below and moved back into his old room upstairs. He complains that His Majesty attacked him. Agnes seizes the opportunity and proposes a deal: She will organize his workshop to find Vortigern’s book if he will enchant a few cats. This, she argues, will fuel the rumors about their shelter, increase adoptions, and serve as compensation for endangering her.

Yannick supports the idea, but Élise remains skeptical and challenges Havelock to prove he was truly responsible for the near-apocalypse three years prior. Provoked, Havelock unleashes a terrifyingly realistic illusion of a destructive storm inside the shelter. The spell quickly becomes difficult for him to control; after the storm, he reassembles the room with the walls and ceiling accidentally swapped. He tries various means to correct it. The display leaves Agnes and Élise shaken but convinced of his power.

Two days later, Agnes begins cataloging Havelock’s workshop. Havelock appears wearing a magical disguise he uses to avoid the authorities, who circulate his image. Agnes explains her systematic approach: She is numbering each Artefact and weighing them, having calculated a weight range for a 17th-century book in case Vortigern’s book is magically disguised. Intrigued, Havelock offers her an enchanted pen that will automatically write down the nature of any spell an Artefact contains.

He teaches her a command word from the language of the Rivenwood. Reluctantly, Agnes holds the pen to her notebook and the gold chain she had been admiring, speaks the command, and performs magic for the first time. The pen, moving her hand, writes that the chain is enchanted to prevent poisoning. The pen scribes this in the handwriting of the original enchanter, an 18th-century magician named Sarah Thomson. The experience of channeling magic is overwhelming, and Agnes begins to cry. In that moment, she realizes two things: She has just performed magic, and she is developing romantic feelings for Havelock. She flees upstairs to Élise, who has already deduced Agnes’s feelings and offers comfort.

The plan to enchant cats is put into motion. Havelock places a simple charm on a kitten to ease minor aches and pains for its new owner. He later enchants two more cats, Chaplin and Baroness, with spells for pleasant dreams and household harmony. 

As the rumors spread, the shelters’ foot traffic and adoption rates increase significantly. Two weeks later, Agnes visits the second shelter and finds it thriving. Mina shows her a large donation from a wealthy patron, which allows them to pay off their veterinary debt to Dr. Para with a little left over.

Agnes meets the man who started the rumors about the enchanted cats: It is Roger Fairwood, the powerful shipping magnate who adopted the cat named Juliette. Shortly after, Detective Laurent Rouzet arrives to see Agnes. He asks her to attend the upcoming winter festival with him, and she accepts.