A shocking truth lies within the pages of an ancient library, locked inside a high-security complex deep beneath the Nevada desert. And the US government will stop at nothing to keep it classified. But now a shadowy group of ex-employees want the world to know — however terrifying the disclosure might prove to be. And when a single volume missing from the original collection mysteriously surfaces at a London auction house, they persuade former FBI agent Will Piper to help them obtain it and unlock the ultimate secret of the library, once and for all. Travelling to England, Will discovers the text contains a sonnet that holds a series of clues — clues that reveal the book has had a profound effect on the history of mankind. But all the time he is being watched. And as he gets nearer to the final revelation, he and his young family become a direct target for a deadly group of men whose duty it is to guard the library's secret — whatever it takes. However, the truth is too powerful to keep hidden...

Abbey of Ruac, rural France: A medieval script is discovered hidden behind an antique bookcase. Badly damaged, it is sent to Paris for restoration, and there literary historian Hugo Pineau begins to read the startling fourteenth-century text. Within its pages lies a fanciful tale of a painted cave and the secrets it contains and a rudimentary map showing its position close to the abbey. Intrigued, Hugo enlists the help of archaeologist Luc Simard and the two men go exploring.

A murderer is on the loose on the streets of New York City: nicknamed the Doomsday Killer, he's claimed six victims in just two weeks, and the city is terrified. Even worse, the police are mystified: the victims have nothing in common, defying all profiling, and all that connects them is that each received a sick postcard in the mail before they died — a postcard that announced their date of death. In desperation, the FBI assigns the case to maverick agent Will Piper, once the most accomplished serial killing expert in the bureau's history, now on a dissolute spiral to retirement.Battling his own demons, Will is soon drawn back into a world he both loves and hates, determined to catch the killer whatever it takes. But his search takes him in a direction he could never have predicted, uncovering a shocking secret that has been closely guarded for centuries. A secret that once lay buried in an underground library beneath an 8th Century monastery, but which has now been unearthed — with deadly consequences. A select few defend the secret of the library with their lives — and as Will closes in on the truth, they are determined to stop him, at any cost.