Sgt. Bowe Bergdahl says he walked off his base in Afghanistan to cause a crisis that would catch the attention of military brass.

He wanted to warn them about what he believed were serious problems with leadership in his unit. And he wanted to prove himself as a real-life action hero, like someone out of a movie.

Bergdahl hasn't spoken publicly about his decision or his subsequent five-year imprisonment by the Taliban and the prisoner swap that secured his return to the United States. But over the past several months he spoke extensively with screenwriter Mark Boal, who shared about 25 hours of the recorded interviews with Sarah Koenig for her popular podcast, "Serial."

"As a private first-class, nobody is going to listen to me," Bergdahl says in the first episode of the podcast, released Thursday. "No one is going to take me serious that an investigation needs to be put underway."

Bergdahl, of Hailey, Idaho, was charged in March with desertion and misbehavior before the enemy. He faces up to life in prison, though an Army officer has recommended that Bergdahl's case be moved to a special misdemeanor-level military court.

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His attorney Eugene Fidell says politicians and would-be politicians have been using Bergdahl as a talking point to push their own agendas for months, a situation he described as creating "gale-force political winds."

The more the public can hear Bergdahl's own words, the better, Fidell told The Associated Press.

"Some of the information that is going to come out is inevitably not going to be what we would have preferred in a perfect universe, but net-net, we'll take it and allow people in our democratic society to form their own opinions," Fidell said.

Bergdahl's interview is another coup for makers of "Serial," which established podcasts as a viable outlet when the first season was downloaded more than 100 million times. Makers wouldn't say how long the new season would last; the first one was 12 separate episodes.

In the episode, Bergdahl says he wanted to expose the "leadership failure" he experienced in Afghanistan. The episode does not elaborate on what that failure was, but he says he believed at the time his disappearance and his plan to reappear at another location would give him access to top officials. After leaving the base after midnight, he worries about the reception he'll get once he reappears, and decides to try to get information on who was planting bombs in the area. That information will help smooth things over with angry military officials, he figures.

Sarah Koenig, the host and executive producer of "Serial," describes Bergdahl as a "radical, idiosyncratic" man in the episode. She says Bergdahl shipped his personal items home, bought local attire and pulled out $300 in U.S. dollars and Afghanis ahead of leaving the base.

Bergdahl acknowledges his motives weren't entirely idealistic.

"I was trying to prove to myself, I was trying to prove to the world, to anybody who used to know me ... I was capable of being what I appeared to be," Bergdahl says. "Doing what I did was me saying I am like Jason Bourne. I had this fantastic idea that I was going to prove to the world I was the real thing."

He says after the sun came up, a group of men on motorcycles captured him as he walked through nearby flatland desert.

He also discusses the psychological torment of being held captive for years.

"It's like how do I explain to a person that just standing in an empty dark room hurts?" Bergdahl recounts. "It's like well, a person asked me, 'Why does it hurt? Does your body hurt?' Yes, your body hurts but it's more than that. It's mental, like, almost confused. ... I would wake up not even remembering what I was."

He adds: "It's like you're standing there, screaming in your mind."