After a catastrophic deployment that left most of his team dead or injured, Nathan Wilde has said his goodbyes to the life of the Green Beret. He is now seeking the quiet life, dedicating himself to his academic passion for history and archaeology--but his hero days are far from over. Nathan's attempt to lead a normal existence is soon threatened by his remarkable discovery of the lost civilisation of Ubar. Catapulted onto the world stage, Nate attracts more than just academic acclaim--mysterious forces are at play, leading to missing friends, summons from world leaders, and conscription back into the military. Knowing he's going back into harm's way, Nate turns to the only men left alive that he truly trusts: his group of tight knit former teammates--a motley crew of expertly trained warriors, to help him navigate the challenges ahead, as well as the demons of his past. Finding themselves hunted by a former Spetsnaz soldier who works for a shadowy organization and chased through the desert by al Qaeda terrorists, the former commandos must utilise their skills in a race to discover whether the city truly exists, as well as uncover a deeper geopolitical mystery that will have resounding ramifications around the world.