In 1986, Lenora retrieves Martin from protective exile in Angola to assist her with an operation selling a shipment of West German weapons to the South African Army. Martin sabotages the sale to General De Graaf when he learns the weapons will be used to attack an oil refinery in Angola and harm people he knows, but Martin reassures a furious Lenora he can negotiate a sale to the Angolans.
Lenora and Martin make arrangements to bring the weapons shipment into Angola. To pay the guide, Gary Banks, Martin sleeps with the West German Trade Commissioner's wife Brigitte Winkelmann and steals her diamond necklace. During the journey, Gary delivers Lenora and Martin into the hands of De Graaf.
Gary takes Martin, Lenora, and a hidden team of rebels into the oil refinery under the pretense of selling the weapons to Major Kalumba. Martin negotiates the sale, and once they have the payment, Gary holds Kalumba at gunpoint, planning to leave with the money, the weapons, and three tankers of diesel, after which the rebels will bomb the refinery. Martin escapes and finds the bomb; he is unable to defuse it in time, but it malfunctions. Gary drops the money, and the rebels all hug each other over it. Lenora and Martin flee, but Martin is shot in the chest by a sniper, and Lenora leaves him for dead.
Gary has taken Martin to recover in Libya, where he is selling the weapons to a terrorist, Khaled Al Badri. Gary also hopes to sell Martin's services as the infamous operative Kolibri. Brigitte is also interested in acquiring Martin and Lenora, and Gary delivers Martin to her. Walter works his way back into the inner circle with a plan to smuggle goods to South Africa. He is about to tell Ingrid that Martin is presumed dead, but changes his mind.
Brigitte is a West German intelligence agent, and has Martin in a hideout in Paris. He declines her offer to be a double agent. Learning Martin may be alive, Walter sends Nina to find him. Martin recognizes Khaled's associate Samira in a photo Nina shows him, and warns Walter she is likely planning a terrorist attack. Walter gets a coded message to US intelligence, who warn their assets in the city. Samira is thwarted in her attempt to bomb the Grand Hotel Voltaire in West Berlin, and instead bombs a nightclub across the street, where Alex and Tim are dancing.
Martin returns to West Berlin, where international intelligence believes he is involved with the bombing. Tim has been seriously injured in the explosion. Walter passes along intel to US agent Hector Valdez proving the Libyans planned the attack without Martin. Lenora blackmails the West German Trade Commissioner Frank Winkelmann into helping her with an arms deal, and brings Rose Seithathi to stay with Ingrid. Martin visits Thomas, who confirms Martin is Max's father. After meeting Thomas, Marianne agrees to help Tina and her family escape East Germany.
Martin is reunited with Tobias, but Annett is not happy with his reappearance. Martin wants to be brought back into East Germany, insisting he is still loyal to the HVA and can be trusted. Barbara Dietrich assigns Lenora to Operation Love Boat. Marianne tries to smuggle Tina and her family across the border, but, thanks to information Martin gives to Annett, they are caught and Marianne is killed.
Martin tells Brigitte he is willing to work for the BND, and she takes him to Mrs Netz, who is now also a West German intelligence agent. Martin's first test of loyalty is to help the BND abduct Lenora. Tobias reveals to Alex he is HIV-positive. Tina is questioned in a Stasi prison. Tobias, representing West Germany, meets Annett to discuss exchanging Martin for several East German prisoners; Annett agrees to exchange Tina, but not her husband or daughters.
Tina is sent to West Germany, but is horrified to learn her family is still in the East. Martin is returned to East Germany carrying BND intel provided by Brigitte. He is reunited first with an icy Annett, and then with his mother. Frank tells Brigitte he is resigning, and that they can move back to Germany together. Martin follows Lenora, who is blackmailed by Frank as she supervises the loading of the weapons to be smuggled aboard the cruise ship. Gary reappears, intent on souring the arms sale, but Rose kills him.
Mrs. Netz arranges passage to West Germany for Martin, Lenora, and Max. The threat of the HVA's smuggling operation being exposed forces Markus if to bring the cruise ship back to East Germany. Lenora is benched. Brigitte tells Frank their marriage is over. Martin abducts Max to coerce Annett to collect Tina's daughters from the orphanage. He sends Lenora and the girls across to West Germany, where they are reunited with Tina and Lenora is taken by the BND. Nina assassinates Frank. Annett lets Martin become a part of Max's life.