Trust No One

The novel opens with a prologue set in 1820. Countess Gabrielle Pauline d'Adhémar, the former lady-in-waiting to Marie-Antoinette, receives a final visit from the Count of Saint-Germain, an eighteenth-century alchemist and polymath famed across European courts. Wounded, he entrusts her with a leatherbound journal secured by copper bands and a crystalline lock, warning that a combustible chemical will ignite the pages if the lock is forced. He vanishes, and the Countess resolves to protect the volume. She dies two years later; the fate of her library remains unknown.

The present-day story centers on Sharyn Karr, a former librarian from Tulsa studying magic and occult science at the University of Exeter. Her roommates are Naomi Wren, a Welsh prodigy with Oxford degrees and a large following on WitchTok, a witchcraft-focused corner of TikTok, and Tag McKnight, a gay man from Edinburgh who has cerebral palsy and holds a master's in biochemistry. Sharyn's father, a police officer with an alcohol addiction, died in a high-speed pursuit, leaving the family in ruin. Despite the verbal abuse she endured, he trained her in self-defense, firearms, lockpicking, and survival skills.

At Exeter's Old Library, Sharyn meets Duncan Maxwell, a wealthy fellow student sixteenth in line to the British throne with an Oxford degree in cybersecurity and AI. In the Rare Books strongroom, Professor Julian Wright, the program director, thrusts a dark copper-bound book with a crystalline orb lock into her hands, orders her to hide it, gives her a business card with a phone number, and warns her to trust no one.

That Halloween, the Old Library catches fire. Armed men storm Sharyn's flat, killing the caretaker. Sharyn leads her friends across rooftops, spotting a Rolls-Royce with Vatican City license plates near the building. The group takes refuge at a nightclub where they find Duncan and his friend Archibald Bailey, a former rugby player whose father served in the British diplomatic corps. Archie confirms the plates belong to Vatican vehicles. When armed men close in, Sharyn pulls a fire alarm, triggering a chaotic evacuation that covers their escape.

Morning news identifies the body in the burned library as Wright, staged inside a pentagram to frame Sharyn. The phone number on Wright's card finally connects to Monsieur Laurent, a stern Frenchman who explains the book is Saint-Germain's journal, fought over for centuries by two secret organizations. The Confrérie des Illuminés, the Brotherhood of the Enlightened, hunts the journal, while the Gardiens du Livre, the Keepers of the Book, protect it. The journal contains three coded sections called Adages: The first, deciphered during World War II, led to ancient gold in North Africa. The second points to the Alps. The third may hold the key to immortality. The group flees to London by train.

The antagonists operate in parallel: Keir Marchand, founder of the biotech firm NeuVentis Pharma, seeks immortality for personal and corporate gain; Saanvi Burman, an MI5 liaison officer, manipulates intelligence resources; and Cardinal Tissot, a Confrérie-affiliated Swiss cleric, claims a mole inside the Gardiens.

The Frenchman's coordinates lead to the Tower of London, where General Sir Ronan Kelly, a Gardiens member who uses a wheelchair, receives them with his daughter Moira and an aged raven called Hugh. Sir Kelly recounts Saint-Germain's history and the Gardiens' effort to decode the journal. Before Monsieur Laurent arrives, attackers disguised as Beefeater Warders, the Tower's ceremonial guards, storm the residence. Sir Kelly stays behind with a pistol while Moira leads the group through secret passages along medieval battlements. A gunman shoots Moira; Hugh attacks the shooter but sustains a wing injury in the process, and Sharyn kills a second gunman with a fallen pistol. Moira commandeers a van as diversion, and the group flees into London.

Laurent arranges passage to France and drives the group to the Château de Barbier near Paris. A former elite paratrooper turned archaeologist whose ancestors were enslaved people freed by the Barbier family, Laurent demonstrates how to open the book using magnets. Duncan applies AI-enhanced codebreaking to the Second Adage, producing a three-dimensional image identified as Monte Antelao, the highest peak in the eastern Dolomites. Tag confirms the location through botanical analysis of flowers on the Adage's title page. When the Gardiens' mainframe is hacked from within, the group flees through tunnels beneath the château.

The Confrérie recovers partial data identifying the mountain and mobilizes toward the Dolomites. Keir assembles mercenaries led by Captain Ferhat. After reaching San Vito di Cadore at the mountain's base, Tag stays behind with Naomi due to his worsening condition while Laurent hires Dr. Bianca Russo, a wildlife biologist accompanied by a Carpathian lynx named Katch, as guide. In town, Keir's forces capture Tag, but Naomi mounts a rescue with local allies, incapacitating Burman in the process.

On the mountain, the group reaches an old World War II bunker. Sharyn realizes headaches on the lower levels stem from toxic mercury vapors seeping through rock. Using the lynx's senses, they trace the toxin to a concealed alcove on the third level. Placing the book inside and opening it with magnets triggers a hidden door, revealing a vault of golden relics from Jerusalem's Second Temple, plundered by the Romans in AD 70: trumpets, shields, the Table of Showbread, and six massive menorahs. A seventh, coated in lead and fronted by liquid mercury, stands apart. Lighting it melts the lead to reveal pure gold, the holiest relic of Judaism hidden beneath an alchemical illusion.

Confrérie soldiers flood the vault. One shoots Keir in the back and removes his helmet: It is Professor Julian Wright, alive and allied with Tissot. Wright confesses to engineering his death, manipulating his selection as the Gardiens' Thirteenth Keeper, and choosing Sharyn as an unwitting courier because he considered her history of abuse a vulnerability. He shoots Russo and demands the book. Instead, Sharyn thrusts the journal into the menorah's flames. As it burns, copper filaments rise and form a three-dimensional map of three islands, with the transformed crystal orb pointing to a bay on the largest. Sharyn memorizes the image before it dissolves.

In the ensuing chaos, the wounded Keir sacrifices himself by hurling a TNT charge back at his betrayers. Katch the lynx attacks Wright and carries him over a cliff to his death. Naomi's earlier plea to Sir Avery Bailey, Archie's father, brings Italian military helicopters that capture Tissot, kill Ferhat, and neutralize the remaining forces. Tag survives and the group is evacuated.

Five months later, the students travel to Malta, equidistant between the two previous sites. At the Sanctuary of Our Lady of Mellieħa, the island's oldest church, Sharyn inserts the transformed crystal into a basin in a buried chapel. The wall opens to reveal a vast underground library descending in tiers, connected by double-helix staircases, its shelves holding thousands of books, scrolls, and artifacts from Saint-Germain's worldwide network. Gilded Latin words on the ceiling urge future generations to study, learn, and grow. Sharyn recognizes this as the true immortality Saint-Germain promised: not eternal life, but knowledge preserved for those who follow.

In a brief coda, a mysterious stranger at the Tower of London cradles Hugh the raven, whispers to him, and tosses him skyward. Hugh's injured wing straightens, and he flies joyfully for the first time since his injury. The stranger vanishes without a trace.