Beneath the forests of Brandenburg lie the bunkers East Germany built to survive a war that never came. Bunker expert Sylvia Rademacher climbs into the Wehrmacht-era Zeppelin bunker at Wünsdorf, once the Soviet armed forces' East German headquarters and later home to the Ranet intelligence center that relayed orders to Moscow, in a district still fenced off as a forbidden town. At Biesenthal, Hans-Jürgen Herget leads a tightly controlled tour through the sprawling Mielke bunker, a hundred-room command post built for the Stasi chief, set against the far simpler shelters prepared for the families of East Germany's political elite in nearby Wandlitz. Near Leipzig, former regime critic Jana Bleyl explores the 4,000-square-meter Stasi bunker at Machern, where original communications and surveillance equipment remains intact. Moving between these three sites, the film reconstructs how East Germany's leadership planned to keep governing, spying, and issuing orders underground if the Cold War turned hot.