Project Horizon: The Nash Shields Thrillers, Rose Sandy, Book 3

Action & adventure, Sci-fi, and Thriller & suspense

Every Silver Gravity story centres women with agency.

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He only needed one day. So did they.

KJ20-Ops agent Nash Shields is a lone wolf for a reason: trust gets you killed. When he stumbles upon an abandoned file in a forgotten NSA vault, he uncovers the impossible: blueprints for technology that can open doorways to parallel universes. Technology worth billions and capable of causing catastrophic glitches in reality itself.

But Nash isn't the only one hunting this power. Mason Laskfell, a ruthless rival from Nash's past, will stop at nothing to harness the technology's reality-bending potential. When Mason kidnaps Nash's former partner and brilliant curator Calla Cress, the stakes become brutally personal.

Nash must assemble an unlikely team, including his one true friend and tech genius Jack Kleve, to mount a desperate rescue mission. From London's shadowy underbelly to ancient stone monuments in the remote Orkney Islands, from the frozen wastelands of Svalbard to a final confrontation in the Arctic Circle, Nash's team races against the clock to prevent reality itself from unravelling.

For Nash, success means confronting the one thing he's avoided his entire career: absolute trust in others. In a world where reality can glitch and enemies become phantoms that walk between worlds, Nash must overcome his deepest fears to save not just those he cares about, but existence itself.

Heart-pounding action, mind-bending sci-fi concepts, and shocking revelations that will leave readers questioning the very nature of reality. Perfect for fans of high-concept spy thrillers.

About the Calla Cress Decrypter Series

The Calla Cress Decrypter Series is a female-led action-adventure techno-thriller series that blends global espionage, cryptography, and high-stakes discovery.

Often compared to a female James Bond crossed with Indiana Jones, the series follows Calla Cress, a brilliant cryptographer and museum curator whose expertise in ancient manuscripts and hidden systems draws her into international conspiracies. As intelligence agencies, criminal networks, and secret organisations collide, Calla is forced to navigate a world where knowledge is power — and decoding the truth can destabilise nations.

Each book stands alone while contributing to a larger arc of global intrigue, making the series perfect for readers who enjoy smart, fast-paced thrillers led by a woman who survives on intellect, courage, and moral clarity rather than brute force alone.

What Kind of Thriller Is This?

This book is best described as a female-led action-adventure techno-thriller.

It combines:

Technothriller elements (cryptography, data, hidden systems, modern intelligence warfare)
Espionage and conspiracy involving governments and shadow organisations
Action-adventure storytelling across global locations
A smart female protagonist whose intelligence drives the plot

If you enjoy thrillers where ideas are as dangerous as weapons — and where discovery triggers global consequences — this series is designed for you.

If You Love James Bond or Indiana Jones…

Readers often compare this series to James Bond and Indiana Jones, but with a modern, female-led twist.

Like James Bond, the story features global stakes, intelligence agencies, and dangerous conspiracies.
Like Indiana Jones, it revolves around ancient knowledge, hidden artefacts, and discoveries that reshape history.

What sets Calla Cress apart is that intelligence is the primary weapon. Codes replace gadgets. Pattern recognition replaces brute force. And the heroine’s strength lies in insight, scepticism, and resolve.

Story Tropes & Reader Appeal

Is This Book for You?

Do I Need to Read the Series in Order?

Each Calla Cress novel is written to stand alone, with its own central mystery and resolution.

However, reading the series in order allows you to follow Calla’s evolving relationships, growing influence, and the wider conspiracy arc that unfolds across the books. New readers can start here, while returning readers will uncover deeper connections.

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

About Rose Sandy

Rose Sandy is an independent author and publisher known for writing female-led action-adventure and techno-thriller fiction.

She is the creator of the Calla Cress Decrypter Series, a globe-spanning techno-thriller series often compared to a female James Bond crossed with Indiana Jones. Her work blends cryptography, global conspiracy, and high-stakes discovery, with a focus on intelligent heroines who survive through insight, courage, and moral clarity.

Rose Sandy’s stories are characterised by fast-paced plots, international settings, and the collision of history, technology, and power. Her fiction is written for readers who enjoy smart thrillers with real-world stakes and strong female protagonists at the centre of the action.