Sierra Six by Mark Greaney

In this gripping thriller, a seasoned operative from the covert Gray Man program finds himself entangled in a deadly mission that spans across continents and decades. As he delves deeper into the shadows of his past, he uncovers a web of betrayal and conspiracy that threatens not only his life but the lives of countless others. With relentless action and unexpected twists, the story explores themes of loyalty, redemption, and the blurred lines between right and wrong in the high-stakes world of espionage.

Purchase from Bookshop.org