The Incandescent

Chetwood School is a centuries-old English boarding school that teaches magic alongside a standard academic curriculum to roughly six hundred students. Dr. Sapphire "Saffy" Walden, a thirty-eight-year-old specialist in invocation (the discipline of demon summoning), serves as Director of Magic, a deputy-head-level role responsible for the school's magical security. In this world, demons are magical life forms drawn to complexity and personhood, ranging from minor imps that possess photocopiers to massive higher demons capable of catastrophic destruction. The school's adolescent students generate enormous ambient magical energy, making Chetwood a constant target for demonic intrusion.

Walden's professional antagonist is Laura Kenning, the school's Chief Marshal and a demon hunter from the ancient Order of Marshals. Kenning clashes with Walden over the education of Nicola "Nikki" Conway, a seventeen-year-old ward of the school and the most talented young magician Walden has encountered. When Nikki was seven, she accidentally triggered a demonic incursion that killed her parents and younger brother. Kenning wants Nikki excluded from advanced summoning lessons; Walden insists Nikki is safer learning under supervision.

During an Upper Sixth practical, Walden's four A-level students attempt a summoning. The class includes Nikki; the careless but charming William "Will" Daubery; the anxious and powerful Mathias Wick; and the academically ambitious Aneeta Shah. When Mathias loses focus, his uncontrolled power attracts Old Faithful, an eleventh-order higher demon that has lurked in Chetwood's magical shadow since at least the seventeenth century. Walden and Kenning drive it back, with Nikki saving them by casting a basic banishment cantrip, a simple emergency spell. Walden notices for the first time that Kenning is genuinely skilled and, as a minor corollary, gorgeous. The near-disaster prompts them to reset their adversarial relationship and begin working together.

Old Faithful whispers to each student during the encounter, telling Nikki it killed her family. Weeks later, Aneeta reveals that Nikki has been secretly researching advanced summoning, planning to confront the demon. Walden races to School House, the students' boarding house, and finds it engulfed in a demonic incursion. Most children have been evacuated, but Nikki and Mathias remain trapped in the tower. Will charges in after them, and Walden follows with Kenning.

Inside, the demonic plane overlaps with mundane reality. After rescuing Will from an archdemon, a high-ranking demon of immense power, Walden sends Kenning and Will back through a portal and continues alone to the tower. She finds Nikki being dragged toward a black void at the center of a summoning array, with Mathias frozen in panic. Walden steps into the void and forces the demon back.

Leading the students toward safety, Walden encounters Old Faithful manifesting in the body of Charlie Green, a student who died in the 2003 incursion at Chetwood. Charlie was Walden's boyfriend when they were both seventeen; they attempted to summon Old Faithful together, and Charlie did not survive. The demon wears his face and taunts everyone present. Walden strikes a blood pact: If the demon lets both students leave unharmed, she will remain and fight it. The students reluctantly go.

Old Faithful overwhelms Walden and pins her down. Kenning returns, blasting the demon away: "GET UP AND GET OUT OF MY WAY!" (127). Walden reveals her final resource: The tattoos on her right arm contain the Phoenix, a tenth-order demon she summoned during doctoral research in Arizona and has kept leashed in her skin for over a decade. She activates the binding, and the Phoenix merges its predatory intelligence with her expertise. Together they destroy Old Faithful; Laura drives her sword through Charlie's chest. Laura then turns the sword on Walden, recognizing the Phoenix as a higher demon, but Walden swears a magical oath: If the Phoenix ever escapes her control, Laura will have all power to act.

The Board of Governors investigates the incursion. Laura volunteers a blunt self-assessment of her failures, then declares Walden irreplaceable, shielding the students from blame. The governors dismiss Laura as a convenient scapegoat and appoint Mark Daubery, Will's uncle, as a charming, well-connected security consultant.

Over the following months, the Phoenix grows increasingly vocal in Walden's mind, learning to read English and grasping that Walden's identity as a teacher drives her generosity toward students. During joint security patrols with Mark, the Phoenix reveals its combat capabilities through Walden's body. At the staff Christmas party, a wild incursion erupts in London; Walden and Laura both respond, containing it with the Phoenix's help. Afterward, Mark kisses Walden, and they sleep together. Laura warns Walden about both Mark and the Phoenix; Walden responds coldly.

In January, a Year Nine student is possessed during class, which should be impossible given the school's defenses. Walden and Todd Cartwright, the school's site manager and Keymaster (the holder of an ancient key that secures Chetwood's oldest magical boundaries), trace the breach to scaffolding that disrupted the wards but cannot explain how multiple protections failed at once. Nikki, in a difficult pastoral conversation about her Oxford offer, suggests someone damaged the defenses on purpose.

This crystallizes months of overlooked evidence. Walden recalls that Mark was out of bed for ninety minutes the morning after they slept together, and the door to the thaumic engines, the Victorian machinery powering the school's defenses, was unlocked. She finds a school umbrella she once gave Mark, now enchanted with a demon-luring curse far beyond the magic he ever displayed. She deduces that Mark works for an organization interested in weaponizing the Phoenix, and that his consultant persona masked a sabotage campaign designed to test its power.

Instead of calling the Marshals or the Headmaster, Walden goes to confront Mark herself. As fury and territorial instinct merge with the Phoenix's predatory nature, something shifts inside her. The novel jumps forward in time.

In a striking narrative shift to second-person present tense, the Phoenix has fully possessed Walden. It inhabits her body, mind, and the institution of Chetwood, while holding Mark in magical stasis. The possessed Walden is a terrifyingly perfected version of the Director of Magic, but the Phoenix's control prevents any adult from perceiving the danger. Only the four Upper Sixth students recognize something is wrong. After months of failed attempts to alert the adults around them, Aneeta proposes they leave school entirely and find Laura at the Marshals' Brixton chapter house in London.

Laura arrives at Chetwood alone on her motorbike. Todd, whose deep attunement to the school grounds makes him resistant to the Phoenix's control, hands Laura the Great Key, an ancient artifact securing Chetwood's oldest magical boundaries. He then smashes the thaumic engines, severing one of the Phoenix's footholds but destabilizing the site, which begins sliding into the demonic realm. The Phoenix battles Laura across burning grounds, drawing power from the landscape itself. A young teacher triggers the fire alarm and begins evacuating four hundred children across the road. Laura, sharpened by six months of academic study under Professor Roger Rollins, holds her ground.

When the Phoenix panics about its crumbling territory, Walden breaks through from within. She thrusts out her right arm, where the Phoenix's binding occupies the entire limb, and begs Laura to cut it off. Laura strikes through the elbow joint with her enchanted sword. Freed from its primary anchor, the Phoenix chooses to stay and stabilize Chetwood rather than escape, preventing the school's collapse into the demonic realm.

Walden wakes in a hospital ward missing her right arm above the elbow. Chief Arjun Ramamurthy of the Marshals confirms that both Walden and Mark survived. Laura visits with a card from the Upper Sixth and a letter from Nikki: Will and Nikki are heading to Oxford for Sorcery, Aneeta to Imperial College for Biochemistry, and Mathias to a Marshal apprenticeship. The Phoenix remains in Chetwood's shadow as a cooperative territorial guardian, and Rollins has brokered a deal for the school's endowment to fund magical teaching at state schools.

Walden tells Laura she does not want to return to Chetwood, admitting she never truly left since she was seventeen. Laura asks her out; Walden says she wants something serious. Laura proposes they try six months together. She wants children; Walden says she could be persuaded. They kiss properly for the first time. Laura answers Walden's self-deprecating warnings: "You're never too old to learn" (414).