The Ghost Agent by Alex Berenson
CIA agent John Wells is back in Washington, recovering from his last mission. His wounds have healed but his mind is far from clear. He is restless, uneasy in his skin, careless with his safety. When the CIA finds evidence of a surge in Taliban activity, backed by an unknown foreign power, it takes little to convince him to go to Afghanistan to investigate. But what Wells discovers there is far from what he expected. A deadly power play in China; a mission in North Korea gone terribly wrong; Iran determined to go nuclear; a mole within the ranks of the CIA who is about to light a fuse. The world is hurtling towards confrontation and, this time, there may be nothing Wells can do to stop it.