Published in 2026, Agnes Aubert’s Mystical Cat Shelter is a cozy fantasy novel by Heather Fawcett, author of the New York Times bestselling Emily Wilde series. The story is set in a magical version of Montréal and centers on Agnes Aubert, a 35-year-old widow whose struggling cat shelter is destroyed in a battle between magicians. Desperate to find a new space before winter, she rents a suspiciously affordable and opulent shop, only to discover it serves as the secret lair for the city’s most feared magician, Havelock Renard, also known as the Witch King. Agnes’s new role as Havelock’s unwitting accomplice draws her into a dangerous world of magical artifacts, feuding sorcerers, and clandestine police investigations.

The novel contrasts the chaotic, world-altering potential of magic with the quiet, grounding force of everyday labor, exploring the theme of The Restorative Power of Domesticity. The story also examines into the dangers of unchecked desire for power, examining Ambition as Moral Corruption through the actions of Havelock’s ruthless sister, Valérie. As the protagonists’ hidden lives are revealed, the narrative explores how Reputation as a Mask for Vulnerability conceals the loneliness and grief of both the unassuming charity worker and the infamous magician.

This guide refers to the 2026 Del Rey first hardcover edition.

Content Warning: The source text and this guide contain depictions of graphic violence, illness, death, and animal cruelty.

Plot Summary

Agnes Aubert, a 35-year-old widow, runs a struggling cat shelter in Montréal called Les Amis des Chats. Her life is upended when a duel between powerful magicians destroys her rented shop on Rue Sainte-Roseline, making it uninhabitable before the onset of winter. Landlords repeatedly reject her attempts to relocate as soon as they learn she houses animals. Frustrated and desperate, Agnes investigates a suspiciously affordable shop on the charming but mysterious Rue des Hirondelles. The landlord’s representative, a nervous young man named Yannick Abrams, gives her a tour of the opulent, historic space. Despite ominous signs, including a persistent smell of fresh bread from a disused oven and Yannick’s warning to stay out of the basement, Agnes’s desperation, compounded by her rescue of two new kittens, convinces her to accept the lease.

Soon after Agnes; her younger sister, Élise; and their volunteer, Mina, move the shelter’s 52 cats into the new location, they become witness to its strangeness. Yannick continues to hang around the shop, and a series of well-dressed, otherworldly visitors begin passing through, using a hidden trapdoor in the back room to access the forbidden basement. Deciding to tolerate this oddity for the sake of the cats, Agnes focuses on running the shelter. The mystery deepens when a handsome and inquisitive police officer, Detective Laurent Rouzet, begins asking questions about the shop’s absent owner. Agnes concludes that the shop previously sold Artefacts, enchanted objects that have been made illegal to possess in Montréal.

One night, a powerful magician named Valérie breaks into the shop. She is searching for Havelock Renard, an infamous and feared dark magician known as the Witch King, and his collection of Artefacts. When Agnes cannot help her, Valérie begins magically destroying the shelter. This prompts a terrifying creature of shadow and flame to emerge from the basement. It transforms into Havelock himself, dressed in pajamas. The magicians duel violently, with Havelock ultimately using an enchantment to blast a defeated Valérie out into the storm. Appalled to find his secret lair overrun with cats, to which he is allergic, Havelock reveals that Yannick is his apprentice and Valérie is his sister. She tracked Havelock via a residual spell from the street duel that damaged Agnes’s old shop. Fearing his sister will return, he performs a powerful “transposition spell,” magically relocating the entire interior of the cat shelter to a new building on Rue Sainte-Sophie, next to the city’s main bank. To cover their tracks from the police who investigate the magical disturbance, Agnes and Havelock invent a cover story. Havelock uses illusion magic to alter the cats’ appearances while Agnes tells Detective Rouzet that this is merely a second branch of their shelter. Though suspicious, Laurent leaves. 

Havelock explains he must travel to the Rivenwood, the dark, forested otherworld that is the source of all magic, to gather power to move the shop back to Rue des Hirondelles. In his absence, Agnes makes the new shelter a success, its wealthy location attracting many adoptions and donations. After Havelock succeeds in returning the shop to Rue des Hirondelles, Agnes, now entangled in his affairs, decides to strike a bargain with him: She will use her formidable organizational skills to catalogue his chaotic, multi-level basement workshop and find a mythical time-travel book by legendary magician Alice Vortigern, which is the Artefact Valérie seeks to become more powerful. In exchange, Havelock agrees to enchant a few cats with minor good-luck charms to fuel the growing rumors of a “mystical” shelter and drive adoptions. The plan is wildly successful, turning the shelter into a media sensation but also drawing the attention of the police, who suspect it as a front for trafficking illegal Artefacts. Laurent asks Agnes on a date, but uses the opportunity to reveal he is also a magician. He arrests her after finding an enchanted pen Havelock gave her for cataloging his collection.

Élise bails a distraught Agnes from jail. Their reunion is cut short when Valérie launches a full-scale assault on the shelter with her apprentices. Believing Havelock is trapped in the Rivenwood, she uses a magical compass to locate Vortigern’s book, which points to the floor of Havelock’s workshop. Havelock returns and battles Valérie’s forces, revealing their inhuman, specter-like true forms. During the fight, Valérie kidnaps Agnes’s beloved semi-feral cat, His Majesty, and escapes through a magical door, leaving Agnes heartbroken. In the destructive aftermath, Agnes has a flash of insight: The compass wasn’t pointing below the workshop floor, but directly above it, to the old baker’s oven in the main shelter. She realizes the book has been hidden there all along, its leaking magic causing the nightly appearance of phantom pastries. With the city on the brink of passing a new bylaw that would empower the police to raid the shelter, Agnes knows she has one chance to end the conflict.

Holding Vortigern’s book, Agnes and a reluctant Élise travel back in time three years to a moment when Valérie and Havelock nearly caused the apocalypse with a world-ending spell. Agnes’s plan is to steal Vortigern’s lantern, a powerful Artefact capable of absorbing magic, which Havelock told her he lost to a mysterious stranger on the second night of the chaos. The journey is emotionally fraught; in the past, Agnes encounters her late husband, Robin, and must force herself to leave him to complete her mission. On Mount Royal, she and Élise find the younger Havelock being attacked by other magicians. Agnes realizes with a shock that she herself is the mysterious stranger from Havelock’s story. In the ensuing chaos, she incapacitates Havelock by throwing a cat at his face and, exploiting his mistaken belief that she is the legendary magician Vortigern, convinces him to give her the lantern. They return to their own time to find Havelock losing the battle against Valérie, whom His Majesty has chosen to stay with and help. Agnes gives Havelock the lantern, and he unleashes its power, which washes over the workshop and strips Valérie and her apprentices of their magic, leaving them powerless.

In the wake of the final battle, Valérie flees. Public opinion, fueled by sympathetic newspaper articles and eyewitness accounts of the fight, shifts dramatically. Havelock is recast from a villain into a reclusive hero who saved the city. The support for the cat shelter forces the city council to abandon the threatening bylaw. The shelter is safe and thrives, expanding its operations and rescuing more cats than ever. Agnes learns the truth of the apocalypse: Havelock created the spell as a young man but never cast it; Valérie stole it and unleashed it, and he secretly took the blame while sacrificing a piece of himself to the Rivenwood to create a counter-spell. 

Though heartbroken, Agnes accepts that His Majesty has chosen to stay with the now-powerless Valérie. Laurent apologizes and, as penance, adopts Ambulance, their most difficult cat. Agnes and Havelock’s relationship deepens, moving from a wary alliance to genuine affection. One evening, he reveals two gifts. The first is an illusion spell that fills the shelter with magical birds at dawn and twilight for the cats’ entertainment. The second is more extraordinary: He has used a complex enchantment to attach the shelter’s attic to an apartment in Paris. He shyly asks Agnes if she would like to visit a café with him there. Overcome with emotion and hope, Agnes accepts and takes her first step into a new city and a future with Havelock.