The Decrypter and The Room of Martyrs: The Calla Cress Decrypter Thriller Series, Book 9 - Rose Sandy

Some secrets beneath the Vatican were meant to stay buried...

When a Vatican archivist discovers a hidden chamber beneath St. Peter's Basilica known only as the "Room of Martyrs," he vanishes without a trace. Inside this forbidden vault lie ancient relics and coded diaries that contain a devastating secret: the martyrs didn't just die for their faith, their blood contains the power to control it.

British Museum curator and covert operative Calla Cress is summoned to Rome, where what begins as a scholarly investigation quickly becomes a desperate race against time. The diaries reveal a dark prophecy: if the martyrs' relics are ever reassembled under one symbol, they could trigger mass religious devotion bordering on mind control.

As Calla deciphers the ancient cryptograms, she experiences vivid visions connecting her to the martyrs' final moments, a genetic ability that makes her both uniquely qualified to understand the threat and dangerously vulnerable to its influence.

Cardinal Severus, a Vatican official with a hidden agenda, is already gathering the scattered relics. Behind him stands the enigmatic Mason Laskfell, a technological genius who plans to amplify the symbol's psychological effects to create the most powerful mind control weapon in history, starting with world religious leaders gathered at an upcoming summit.

When Calla discovers the final component hidden in the British Museum's collection—protected by her own family for generations, the case becomes devastatingly personal. The coded diaries suggest her miscarriage wasn't natural but a calculated intervention to prevent a child genetically resistant to the symbol's power.

With her partner Nash Shields, an elite NSA tactical operative with his own connection to the case, Calla must navigate Vatican politics, ancient rituals, and cutting-edge technology to prevent a global catastrophe. From Rome's ancient catacombs to London's historic churches, from forbidden Vatican archives to a high-tech summit where minds will be controlled and faith weaponized, Calla races to stop those who would transform humanity's greatest strength, belief itself, into its greatest vulnerability.

In her most dangerous mission yet, Calla Cress confronts the thin line between faith and manipulation, devotion and control—while facing an enemy who understands that the most powerful weapon ever created isn't forged from steel or science, but from the very blood of believers.

ROOM OF MARTYRS is the electrifying installment in the internationally bestselling Calla Cress series, perfect for fans of Dan Brown, James Rollins, and Steve Berry.

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