ed lavandera looks back to when bergdahl vanished from the battlefield. >> reporter: the night bowe bergdahl disappeared in the summer of 2009, he was 23 years old. the army sergeant's gun, bullet proof vest and his night vision googles were found in his bunk. from that moment, the u.s. military would spend five years looking for and negotiating for his release. >> our commanders are sparing no effort to find this young soldier. >> reporter: it's a saga that still isn't over for the soldier, who is now 28 years old. when bowe bergdahl disappeared, he was stationed at a u.s. military outpost in southeastern afghanistan. he was supposed to be on a guard shift that night. this was his first deployment as a u.s. soldier, and he had been in afghanistan less than two months. other soldiers in his unit have described bergdahl as a deserter and a traitor to his country. >> i think he just wanted to go on an adventure without having