Gunner

S1, E5: Frank finds one of his former squad-mates, Gunner Henderson, in hiding in Kentucky, which leads to his discovery that Agent Orange is CIA Director of Covert Operations William Rawlins. Frank and Gunner are ambushed by a team acting under Agent Rawlin's orders and are badly wounded. Worse yet, the cameras on the soldiers' uniforms reveal to Rawlins that Frank is still alive.