Calla Cress is no ordinary museum curator. By day, she manages ancient manuscripts, Byzantine relics, and rare artifacts at the British Museum. But in the shadows, she’s a top operative, for a covert multi-government spy agency. With unparalleled skills in cryptography, ancient languages, and digital intelligence, Calla is known asThe Decrypter,the one they call when the stakes are global and the clues are buried deep in history.

The Calla Cress Technothriller Series

Introduction: The Curator and the Code

Calla Cress is a brilliant curator at the British Museum, a woman whose unparalleled command of history and ancient languages has made her a luminary in the academic world. Her quiet life shatters when she’s recruited to decipher a cryptic, long-lost manuscript written in an apparently unbreakable code. The secrets locked inside are no mere curiosities: they map the location of resources that could make crude oil look obsolete. Thrust from scholarly halls into the shadows of global espionage, Calla learns that priceless artefacts can be triggers for future wars—and her first mission is only the beginning.

The Scope of the Conspiracy: A Global Race Against Time

What starts with a single manuscript escalates into a worldwide battle against a cascade of interlinked threats. The Calla Cress series blends historical mystery, high-stakes international espionage, and cutting-edge technothriller energy. From London and Paris to the deserts of Morocco and the jungles of the Congo, Calla and her allies piece together clues centuries in the making. Hunted at every turn by relentless foes—wielding carbonado diamonds and moving like computer-augmented phantoms—they bend physics and technology to their will. With each book, the stakes rise and the pace accelerates, as Calla uncovers a conspiracy vast enough to bring the world to its knees.

A Promise to the Reader: Unforgettable Adventure

Expect an action-packed ride from first page to last—breathless momentum with brains and heart. Each instalment delivers intricate mystery, breathtaking suspense, and relentless thrills. If you love globe-trotting puzzles, fierce heroines, and technothrillers that never let up, the Calla Cress series belongs on your shelf.

Main Characters

Calla Cress—the series protagonist—is a British Museum curator and ISTF agent on a personal crusade to uncover her origins and the truth behind her genetically enhanced abilities. Facing cryptic codes and dangerous foes, her journey pushes her cyber-espionage skills to the limit. Across the series she evolves into a formidable operative, determined to reconcile the mysteries of her past with her present while battling adversaries who weaponise her own secrets against her.

Jack Kleve is the quintessential ally—a visionary tech entrepreneur and ISTF operative who lends his skills to Calla Cress and Nash Shields. While navigating corporate rivalry and the murky ethics of rapid technological advancement, his arc bends towards recognising the greater good over profit. Jack’s devotion to Calla adds a personal dimension to his conflicts, intertwining the professional with the emotional. His shift from profit-driven inventor to socially conscious partner marks a pivotal transformation in the series.

Nash Shields, an NSA and ISTF agent, is the steadfast protector and love interest, driven by a profound sense of duty. He confronts formidable enemies and complex political networks while safeguarding vital technologies alongside Calla. His journey forces him to question the ethics of his mission, balancing loyalty to his agencies with a deepening moral awareness. Torn between professional duty and personal feelings, Nash walks a precarious line between love and allegiance.

The Calla Cress Decrypter Thriller Series In Order

• Book 1: Secret of the Lost
  Manuscript
• Book 2: The Mind Hacker
• Book 3: Digital Eyes Only
• Book 4: The Storm’s Eye
• Book 5: The Pythagoras Clause
• Book 6: The Beale Ciphers
• Book 7: Atlantis of the Sands
• Book 8: Kingdom of Diamonds
• Book 9: The Falcom Syndrome
• Book 10: The Queen of Sheba
• Book 11: The Calculus Warning
• Book 12: The Cobra Paradox
• Book 13: Room of Martyrs
• Book 14: Eiger Mosaic
• Book 15: Enemy of Wolves
• Book 16: The Pharaoh's Mask
• Book 17: The Eternity
  Hypothesis
• Book 18: The Sculptor's Code
• Book 19: The Solomon Agenda
• Book 20: The Pheonix Cipher
• Book 21: The Cairo Key
• Book 22: Red Fox Agenda
• Book 23: Phaistos Disc
• Book 24: Scorpion Gold

Mind Hacker sample.

Meet the Author  Rose Sandy

Rose Sandy writes thrillers that blend espionage, technology, and history into fast-paced adventures. Her stories dive into the world of covert intelligence, scientific breakthroughs, and global conspiracies, perfect for readers who love suspense with a twist of "what if?" Whether you're on a morning commute or relaxing on a Sunday, her books promise to entertain, surprise, and transport you to hidden corners of the world.

A true globetrotter and lifelong communicator, Rose draws inspiration from historical archives, cutting-edge tech, and conversations with intelligence insiders. When she's not researching in the British Library or exploring Churchill’s War Rooms, she’s crafting thrillers that weave intrigue, action, and a hint of romance. Discover more here or join her newsletter at subscribepage.io/Wuqko4.

action-packed female lead, globe-trotting techno-thriller, ancient technology meets modern espionage, race against time, found family spy team, enemies in high places, codebreaker heroine, secret government experiments, weaponised weather conspiracy, thrilling archaeological mystery, intelligent action thriller, morally complex allies

Action & Adventure, Thrillers, Conspiracy Thrillers, Technothrillers, Espionage Thrillers, Mystery & Suspense, International Crime, Historical Thrillers, Women Sleuths, Cyber Thriller, Archaeological Thrillers, Political Thrillers