Action & adventure, Thriller & suspense, Romance, Sci-fi, Technology, History, Fantasy, Historical fiction, Travel, and Suspense
Every Silver Gravity story centres women with agency.
Three Cryptic Codes. One Fearless Heroine. Infinite Danger.
If you love globe-trotting thrillers packed with ancient mysteries, high-stakes espionage, and a brilliant heroine who outsmarts everyone in the room, this is the bundle you have been waiting for.
Books 13, 14, and 15 in the bestselling Calla Cress Decrypter Thriller Series by Rose Sandy, collected in one unmissable ebook bundle. Calla Cress, British Museum curator, elite codebreaker, and covert ISTF operative, is back, and the stakes have never been higher.
Book 13: The Room of Martyrs
When a Vatican archivist vanishes after discovering a hidden chamber beneath St. Peter's Basilica, Calla Cress is summoned to Rome. Inside the forbidden vault lie ancient relics and coded diaries holding a devastating secret: the martyrs' blood carries the power to control belief itself. As Calla deciphers the ancient cryptograms, she experiences vivid visions connecting her to the martyrs' final moments, a genetic ability that makes her uniquely qualified to understand the threat and dangerously vulnerable to its influence. With a global religious summit in the crosshairs and a technological genius poised to weaponise faith on a mass scale, Calla must stop the most insidious mind control weapon ever conceived before it is too late.
Locations: Vatican Secret Archives, Rome, ancient catacombs, British Museum, London
Book 14: The Eiger Mosaic
When satellite images reveal a mysterious mosaic carved into the treacherous north face of the Eiger, Calla recognises what others cannot: a complex cipher hidden in plain sight for over seventy years. The Alpine Cipher, a legendary WWII encryption key thought lost forever, is resurfacing alongside technology decades ahead of its time. With a catastrophic winter storm approaching and mercenaries closing in, Calla must conquer her fear of heights and scale the Eiger's deadly north face to reach the truth first. What her parents died protecting, she must now find. What others would kill to possess, she alone can decode.
Locations: Swiss Alps, Eiger north face, hidden WWII bunkers beneath the ice
Book 15: Enemy of Wolves
When digital wolves appear in augmented reality apps worldwide and infrastructure crumbles in their wake, Calla recognises something impossible embedded in the attack: ancient Nordic runes controlling modern networks. As global cities plunge into chaos, she traces the threat to a radical eco-terrorist group whose charismatic leader believes she has found the path to restoring natural balance by dismantling technological civilisation. But a darker mind manipulates the cause from behind prison walls, and when Freya delivers a chilling message about Calla's unborn child, the mission becomes devastatingly personal. With Arctic ice melting to reveal an ancient facility where technology and nature have impossibly merged, Calla faces a choice that will determine the future of humanity itself.
Locations: Global cities, Arctic wilderness, ancient subglacial facility
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, Matthew Reilly, Wilbur Smith, female-led action thrillers, archaeological mystery, techno-thriller
Bundle and Save, get all three ebooks in one purchase and dive straight into the next chapter of Calla's world. 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.
