The Quotient Series

Join Jack and Sarah as they race to save humanity in this techno-thriller series by Gregory R. Simpson.

The Books

The Quantum Contingent book cover

The Quantum Contingent

A fast-paced techno-thriller weaving together quantum computing, espionage, drone warfare, and global stakes. Follow Jack and Sarah as they uncover a conspiracy that could reshape the world.

Quantum Time book cover

Quantum Time

The gripping sequel deepens the world of the Quotient series. Available in ebook, paperback, and audiobook — narrated by the author himself.

Quantum Launch - Coming 2027

Quantum Launch

The prequel to the Quotient Series. Learn how Quotient formed and the backstory on some of your favorite members of the team! Coming 2027.

Praise for the Series

★★★★★
"A riveting techno-thriller that blends cutting-edge science with pulse-pounding espionage. Simpson's vivid imagery and exciting dialogues make for a gripping read that keeps you on the edge of your seat from start to finish."
— Rabia Tanveer, Readers' Favorite, on The Quantum Contingent
★★★★★
"A masterfully crafted sequel that will appeal to lovers of time travel, sci-fi, and espionage thrillers. Simpson delivers spell-binding plot twists and deeply human characters facing seemingly invincible villains. A must-read for fans of the genre."
— Keith Mbuya, Readers' Favorite, on Quantum Time
Gregory R. Simpson

Gregory R. Simpson

Greg writes fast-paced techno-thrillers blending espionage, technology, and high-stakes action. A former CTO with 37+ years in technology, he brings authentic depth to every page.

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