Episode 3 of "Unfamiliar" commences in Belarus, sixteen years ago. Simon and Meret escort Josef and Katya to the secret hideout, subsequently venturing back into the open. Within the safety of their refuge, Gregor and Katya turn their backs on Josef. Gregor declares that he'll dispatch Katya and her infant to Berlin, but Josef must embark on a treacherous mission to Russia as a spy under his command. Josef triumphs over Gregor by shooting him down and forces Katya to imbibe poison for her betrayal.
In the present, Josef interrogates Gregor, who divulges that one of their agents was a doctor who miraculously saved the baby. He even surrenders Karl and Helena's real identities, though he asserts ignorance about their current whereabouts. In the bustling city, Meret is tailing Jonas, only to be caught in a chase. Simon intervenes, rescuing her just in time. Meret manages to trap Jonas' car before fleeing with Simon. He spots her and waves, which she reciprocates. When Simon enquires if she recognizes him, she feigns ignorance.
At the BND, Julika informs Alice of her suspicion that Ben is a mole. The team learns about Jonas' morning car chase, and Julika discovers CCTV footage revealing Helena Kohn. They decide to investigate her further.
Meanwhile, Gregor manages to break a glass bottle and uses its shards to free himself. He even locates a phone and attempts to access a portal but gets caught. Josef demands to know the password to his account, but Gregor remains tight-lipped.
Back at home, Meret confronts Simon about his aneurysm in front of his restaurant employees, including Yul, a close associate of Nina. Yul receives a voicemail from Nina expressing her absence from Paris and requesting a meeting. Yul complies and informs Nina about the aneurysm. Nina assumes it's the same condition her parents have been worried about.
Vera converses with her father and realizes she's merely a cover for Josef to be in the city as a handler for the BND mole. Unwilling to lose her position, Vera decides to take matters into her own hands.
At home, Meret endeavors to comprehend Simon's reluctance towards the surgery aimed at removing the aneurysm. He candidly confesses his fear of mortality during the operation. Ben and Julika confront Jonas, probing him with questions, yet he remains tight-lipped. Frustration sets in for Ben when he learns that Julika and Alice had discovered dash cam footage of Josef's meeting with Jonas but had chosen to keep it from him.
Jonas meets with Josef once again, threatening Vera to reciprocate Josef's intimidation of his children. Josef then sits with Vera, who informs him that the committee has given him the green light and that he no longer needs to worry about Belarus. She reveals that she sold their apartment and bribed the committee members.
Simon and Meret visit Katya at the safe house, urging her to flee the country. However, she is hesitant to leave without confronting Josef first.
At the BND, Alice attempts to reconcile with Julika, but Julika remains uninterested. Later, Ben makes amends for their earlier disagreement with Julika, while Alice observes them from afar.
Meanwhile, Josef obtains the password from Gregor. He stabs Gregor in the thigh and sends a picture to Meret, setting a trap. Despite knowing it's a trap, Simon and Meret decide to go ahead, even offering Katya a chance to confront Josef. Jonas and his team are part of the trap. When a car approaches, Katya emerges, catching Josef off guard. Josef orders his men to capture Katya alive. As Simon also steps out of the car, Meret takes down one of Jonas' snipers and engages in a fierce battle with his men. She and Simon manage to defeat them all, while Josef descends to the street to confront Katya. As they stare at each other, Simon and Meret return to the car, and Meret drives them away from the scene. Simon questions her actions since it wasn't part of their plan.
