23-year-old Martin Rauch is sent to West Germany to act as a spy, gathering intelligence for East Germany's Secret Service.

Martin is ordered to break into the hotel room of a high-ranking NATO official and steal a top-secret report.

While at a NATO conference in Brussels, Martin gets his first assignment: to seduce and bug the head security analyst’s secretary, Linda.

When the bug is found in Linda's desk, NATO is placed on high alert. Linda arrives to visit Martin, who scrambles to turn her loyalties around.

Martin is sent back to East Berlin, but is forced to deliver a seemingly harmless package to a mysterious man in West Berlin on the way.

When Moritz returns to his undercover life in West Germany he is drawn into Alex Edel’s fatal plans. Recovering in a room at Charite, Moritz encounters Annett for the first time since he left. He wants to stay home now, she tells him to go West again. Much is left unsaid. She is now in with Schweppenstette, who visits him next and insists, in a tense, father-son coded argument, that Moritz return to his post. Meanwhile Alex Edel has taken General Jackson hostage and forced him, at gunpoint, to film a seething denouncement of US military plans in Western Europe. Lenora follows the whole thing over the wire from the StäV. But by the time Moritz and Kramer get there to break them out before the Police arrive, the damage is already done.

As preparations for NATO's nuclear war game "Able Archer" intensify, Martin receives an order from East Germany that cements his fears about their paranoia. He must warn his Western superiors about the misunderstanding.

​Fear of a pre-emptive nuclear strike against the West has become a possibility at East German HQ, while in the West, war game Able Archer reaches its peak. Martin is now persona non grata on both sides of the border.