SILENT THUNDERIt was the assignment of a lifetime.... Brilliant marine architect Hannah Bryson has been given a priceless opportunity. A U.S. maritime museum has just acquired the former pride of the Soviet fleet, the decommissioned submarine Silent Thunder, for public exhibition. Hannah must inspect every single inch of this legendary nuclear attack sub and design modifications that will make it safe for the thousands of expected visitors. Enlisting the aid of her brother, Connor, they examine the enormous vessel and delve into its long and lethal history. But it was a trap.... On a routine check, Connor discovers a mysterious message behind one of the ship's panels. But before he can figure out what it means, there's a deadly assault on Silent Thunder.... The U.S. government warns Hannah against it, but she'll stop at nothing to find the ruthless mastermind behind the plot. Even if it means joining forces with a mysterious man who may be even more dangerous than the enemy she has sworn to bring down. As Hannah finds herself caught in the crossfire of an epic standoff, her only hope for survival is to unravel Silent Thunder's explosive secret. But someone's willing to kill to make sure Silent Thunder stays silent.... SHADOW ZONEDeep below the deceptively beautiful waters of the Atlantic Ocean, guarded by hundreds of dolphins, lie the astonishing remains of a mysterious lost city much like the legendary Atlantis. While mapping the ancient underwater metropolis of Marinth, marine architect Hannah Bryson makes a shocking discovery: She may have finally uncovered the truth about the once-glorious city's mysterious demise. Marinth's sudden disappearance has confounded scientists for years, but now, with the revelation of a key artifact, Hannah realizes that the long-buried city's explosive secret could have dire consequences for the modern-day world. But she isn't the only one who realizes it. The artifact is hijacked, and Hannah stands alone between a power-hungry enemy and widespread destruction. Willing to form whatever alliance is necessary to regain control of this potentially world-changing weapon, Hannah joins forces with Nicholas Kirov, a loose cannon from her past who is now her best hope for survival. Together they will race to unravel Marinth's last great secret in order to prevent a catastrophe of global proportions. And before the lethal game is over, Hannah will realize that nothing and no one is what she expected, not even the dolphins, who know so much more than anyone could imagine.