Former Army Ranger Tucker Wayne and his war dog Kane are thrust into a global conspiracy that threatens to shake the foundations of American democracy in this second exciting Sigma Force spinoff adventure from New York Times bestselling authors James Rollins and Grant Blackwood.

Tucker Wayne's past and his present collide when a former army colleague comes to him for help. She's on the run from brutal assassins hunting her and her son. To keep them safe, Tucker must discover who killed a brilliant young idealist--a crime that leads back to the most powerful figures in the...

From bestselling authors James Rollins and Grant Blackwood, the first installment in an exciting new thriller series based on the Sigma Force novels featuring former Army Ranger Tucker Wayne and his partner, Army working dog Kane, introduced in the New York Times bestseller Bloodline and the e-original story "Tracker."

Former Army Ranger Tucker Wayne and his military working dog Kane are recruited by Sigma Force to extract a Russian pharmaceutical magnate from Siberia. A scientific genius, the drug tycoon holds the biological key to a new weapon system, a danger...