In the middle of the night, Pfc. Bowe Bergdahl grabs a notebook, snacks, water, some cash. Then he quietly slips off a remote U.S. Army outpost in eastern Afghanistan and into the dark, open desert. About 20 minutes later, it occurs to him: he’s in over his head.  Our newest podcast, “The Preventionist” is out now. Search for it wherever you get your podcasts.To get full access to this and other Serial Productions and New York Times podcasts on Apple Podcasts and Spotify, subscribe at nytimes.com/podcasts.To find out about new shows from Serial Productions, and get a look behind the scenes, sign up for our newsletter at nytimes.com/serialnewsletter.Have a story pitch, a tip, or feedback on our shows? Email us at serialshows@nytimes.com