The Wren in the Holly Library

The first installment in a fantasy romance series, the novel is set in a post-apocalyptic New York City where, thirteen years earlier, monsters revealed themselves to the world. A decade-long Monster War devastated civilization before a fragile Monster Treaty restored an uneasy peace. The city is now fractured between wealthy neighborhoods where humans and monsters coexist and impoverished districts ruled by gangs and underground economies.

Kierse McKenna, a twenty-five-year-old thief, breaks into a mysterious Upper West Side brownstone to steal a diamond ring for a client. Inside, she discovers an enormous private library called the Holly Library, its shelves threaded with living holly vines. She cracks the safe and pockets the ring, but the brownstone's owner, a powerful monster who introduces himself as Graves, catches her mid-escape. Pale and sharp-featured, he radiates an intense heat she cannot place among any known monster type. When he touches her throat, expecting to use some power, he recoils in shock and asks what she is. Kierse, who believes herself fully human, has no answer. Graves lets her leave with the ring and offers her a job stealing something far more valuable.

Kierse lives in the attic of a Lower East Side brothel run by Madame Colette, alongside her two closest friends: Genesis (Gen), Colette's daughter, who has partial vision loss and reads tarot cards, and Ethan, a young man scarred by past abuse. She tells them Graves claims she has magic and that his house was protected by invisible magical barriers called wards that she passed through without effort. Before they can discuss further, the Druids, a Brooklyn gang led by Lorcan Flynn, raid the brothel. Kierse fights off attackers and flees with her friends to Five Points, the nightclub headquarters of the Dreadlords, a werewolf pack led by alpha Nate O'Connor, a charismatic Irish-American werewolf Kierse once worked for.

Nate reveals that Graves helped broker the Monster Treaty and trades in information. He advises Kierse to take the job on her own terms. Kierse negotiates: ten million dollars, protection for Gen and Ethan, and information about her own nature. Graves explains that she nullifies magic, which is why she passes through his wards unharmed. The job is to steal the Spear of Lugh, a mythological weapon, from King Louis, a vampire who leads the Men of Valor, a violent anti-Treaty organization, during a winter solstice party in their underground stronghold called Third Floor. She must live in Graves's brownstone, train in spear combat with his butler Edgar, and, to protect Gen and Ethan from retaliation, cut all contact with them.

Kierse secretly distributes cash and burner phones to Colette and Nate, privately gathering intelligence from all sides to prepare for future conflict. As a test, Graves brings her to a party in Chicago hosted by fellow warlocks Imani and Montrell Cato. Kierse poses as Graves's lover, and a possessive kiss blurs the line between performance and attraction. She breaks into a warded vault and retrieves personal letters but inhales a lethal variant of wish powder, a substance imbued with Imani's wish-granting magic, that nearly kills her. Graves administers an antidote. The letters turn out to be personal correspondence rather than intelligence for the heist, revealing that Graves used the mission to settle a private score.

Graves's mentor, Kingston Darby, a centuries-old master warlock, visits and teaches Kierse that warlocks recharge through a specific activity: Graves through reading, Kierse through stealing. Kierse and Graves have sex for the first time in the Holly Library, shifting their relationship from professional to personal. Graves reveals his main power: He can read people's memories through skin contact, which is why he always wears gloves. His power does not work on Kierse. At The Covenant, a monster hospital, Dr. Emmaline Mafi delivers a startling finding: Kierse is neither warlock nor human, her DNA matches no known species, and her body actively absorbs magic. Unknown to Kierse and Graves, Dr. Mafi is being blackmailed by King Louis and sends Kierse's blood samples to the vampire king.

Lorcan intercepts Kierse and takes her to dinner, presenting himself as the hero opposing Graves and claiming they were once like brothers. Kierse plays along, feeding him half-truths. She begins reconnaissance of Third Floor, a sprawling underground monster market beneath Grand Central Terminal, passing through warded checkpoints created by Walter Rodriguez, Graves's former warlock apprentice whose magic now protects King Louis's domain. In the market, Kierse finds her ex-girlfriend Torra alive but weakened in a blood brothel called Red Velvet, indentured to King Louis after being kidnapped a year earlier. Kierse kills the vampire responsible and secures Torra's help smuggling her into the solstice party.

When Ethan is drugged with wish powder at Five Points, Kierse rushes to help, and Graves discovers she has maintained secret contact with the Dreadlords. Furious, he tells her not to return. Under the pressure of saving Ethan's life, Kierse's magical senses fully awaken. She absorbs the wish powder from his body through touch, aided by a spiritual connection that forms among her, Gen, and Ethan. She saves Ethan but cannot save three wolves who die from the overload. After a three-day collapse, she successfully creates her first ward, seeing a wren symbol within it. She returns to the brownstone, and she and Graves reconcile by sharing their deepest secrets: her history of abuse at the hands of her former mentor, and his centuries-long life of abandonment beginning with his birth in 1509.

On the winter solstice, Kierse infiltrates King Louis's party disguised as a Red Velvet worker while Graves enters through a secret tunnel she mapped earlier. They crack Walter's ward system and open the vault, but an alarm traps Kierse inside. Captured and brought before King Louis, she is bitten; the vampire king has learned from Dr. Mafi's samples that Kierse's blood enhances his power. Kierse grasps the Spear of Lugh through its warded case, and its power surges through her, burning off the venom and amplifying her abilities. She fights and decapitates King Louis, then escapes with Graves and Torra. Outside, Torra walks away to begin her new life.

Back at the brownstone, Graves reveals he possesses the Sword of Truth, a second mythological artifact, and is collecting all four treasures of the Tuatha Dé Danann, a supernatural race from Celtic mythology, for a spell he refuses to explain. They return to find Lorcan waiting with Druids holding Gen and Ethan at knifepoint. Lorcan reveals himself as the Oak King; Graves is the Holly King, his seasonal counterpart in a myth of gods who battle on the solstices. Lorcan demands both artifacts and accuses Graves of murdering his teenage sister Emilie. Graves uses the Sword of Truth on Kierse, breaking a hidden magical binding and revealing her true identity: She is a will-o-the-wisp, the last surviving member of an ancient supernatural fairy race believed massacred to extinction. Kierse, furious that Graves suspected this for weeks and withheld it, claims the spear by birthright.

Lorcan wins the ensuing sword fight, claiming the Sword of Truth. When he strikes the final blow of Oak King ascendance, Kierse interposes herself to protect Graves, and god-level seasonal magic overwhelms her body. Her heart stops. Gen and Ethan place their hands over Kierse's heart, activating a triskel, a triple-spiral bond linking Ethan as a Druid, Gen as a High Priestess, and Kierse as wisp. The bond channels the lethal energy from Kierse's body, and her heart restarts.

In the aftermath, Lorcan departs with both swords. Ethan decides to stay and train with Lorcan in Druidic magic. Graves asks Kierse to stay, but she declines, needing to find answers about her heritage on her own terms. Both Graves and Lorcan direct her to the Goblin Market, a supernatural marketplace on Grafton Street in Dublin. Gen accompanies Kierse, who keeps the spear by birthright. A final interlude shows Graves alone in his library when a contact calls to report the third artifact, a cauldron, has been located, setting the stage for subsequent volumes.