Thriller & suspense, Travel, Technology, History, Action & adventure, Crime & mystery, and Suspense
Every Silver Gravity story centres women with agency.
Six Cryptic Codes. One Fearless Heroine. Infinite Danger.
If you love globe-trotting thrillers packed with unbreakable ciphers, high-stakes espionage, and a brilliant heroine who outsmarts everyone in the room, this is the bundle you have been waiting for.
Books 1 through 6 in the internationally bestselling Calla Cress Decrypter Thriller Series by Rose Sandy, collected in one unmissable ebook bundle. Meet Calla Cress, the British Museum's most brilliant curator and the government's most closely guarded secret. Six adventures. One extraordinary woman. Start from the very beginning.
Book 1: Secret of the Lost Manuscript
A priceless manuscript vanishes from a Berlin vault. The cipher it contains has never been broken. And the only person who can decode it is a woman who does not yet know who she really is. When Calla is pulled into a race across Europe to recover the manuscript before it falls into the wrong hands, she uncovers something far more dangerous than stolen history: the truth about herself.
Locations: Berlin, across Europe
Book 2: The Mind Hacker
She chose not to kill him. Now the world is paying the price. The world's brightest minds are falling into comas. Governments are being brought to their knees by cyber attacks of surgical precision. And the man responsible is doing it all from a high-security prison cell. Pulled back into the field after an explosion destroys her Colorado safe house, Calla finds herself hunted by a powerful organisation demanding answers about a missing MI6 agent. Racing across continents with NSA advisor Nash Shields and tech entrepreneur Jack Kleve, she must confront a weapon unlike any other, one that turns the human mind against itself.
Locations: Colorado, across continents
Book 3: Digital Eyes Only
The NSA's most dangerous secrets are for sale. Only one person can stop the auction. When Calla is summoned to Downing Street to decrypt a classified communication, what begins as a contained security crisis quickly unravels into something far darker. A device stolen from the NSA's most restricted vault contains codes for technologies the world is not ready for, and it is about to be sold to the highest bidder on the darknet. The trail leads from the corridors of Westminster to the sun-bleached fortresses of Malta, from Monte Carlo's gilded rooms to a Bavarian castle hiding secrets beneath its foundations.
Locations: London, Malta, Monte Carlo, Bavaria
Book 4: The Storm's Eye
An island. A vanished team. A technology that commands the weather itself. When an elite group of international scientists disappears from a classified facility on a remote Pacific island, Calla is deployed alongside an ex-Marine intelligence officer and a genius engineer to find them. What they discover defies every assumption about what is possible, and what should never have been built. Calla races to stop a weapon that does not fire bullets. It controls storms.
Locations: Hawaii, St. Petersburg, Miami, Atlantic coast of Portugal
Book 5: The Pythagoras Clause
You download the app. It predicts your future. Then you never wake up. A horoscope app is predicting real events with impossible accuracy and leaving its users in comas. When it delivers a warning about Calla herself, she knows this is no coincidence. Someone has resurrected a lost algorithm rooted in the mathematics of Pythagoras, one that does not just predict the future. It removes the possibility of any other one. Calla follows a trail of ancient ciphers and cutting-edge AI to reach the one man determined to use mathematics to master destiny itself.
Locations: Istanbul, Havana, Kenya, Caribbean
Book 6: The Beale Ciphers
Two hundred years ago, a man hid a fortune and left behind three encrypted letters. No one has cracked them. Until now. When Calla and her closest friend Jack Kleve uncover ancient wall paintings and a hidden telescope deep inside a New Mexico cave, they realise the Beale Ciphers do not lead to gold. They lead to something far more dangerous. Then the cave collapses. Jack vanishes. And Calla is named the prime suspect in his disappearance. Forced to run and hunted by her own government, she follows Jack's final clues across continents to decode a centuries-old secret guarded by people who will kill to keep it buried.
Locations: New Mexico, Chihuahua Desert, North Africa, Atlantic coast
Fans of this series love:
- Race against time
- Ancient secrets with modern consequences
- Globe-trotting adventure across iconic locations
- Ciphers, puzzles and codebreaking
- Secret societies and shadowy enemies
- High-tech espionage meets historical conspiracy
- An unstoppable, brilliant heroine
- Betrayal, found family and reluctant allies
- World-at-stake stakes
Perfect for readers who love:
Dan Brown, Steve Berry, James Rollins, Scott Mariani, Ernest Dempsey, Clive Cussler, female-led action thrillers, cryptographic mystery, techno-thriller
Bundle and Save, get all six ebooks in one purchase and dive straight into Calla's world from the very beginning. No waiting. No gaps. Just pure, unputdownable thriller fiction.
Add to cart and start reading today.
For the physical book bundles, check the Bundles drop-down menu.
