Helene Sonntag, 40, unmarried and a teacher. She has long dreamed of happy partnership, but things turn out as they should. In order to avoid the work overload caused by substitute teaching and vacation childcare, she is forced to make a move.

Enemy secret services from the West had used modern technology for the "cold war", i.e. the confrontation with the Eastern Bloc, and developed a device called COMMINT 3-72. Its nickname was "Radiokiller". This weapon was not much bigger than a soccer and could be easily camouflaged on the territory of the GDR, for example as a fieldstone, the remains of a wall or a lump of earth. These enemy objects were inconspicuous on the outside, but packed with complicated inner workings, i.e. highly sophisticated microelectronics.

Early 1921: a man is on his way home. Gleb Chumalov, regimental commander, worker and Hero of the Order of the Red Banner, returns to his home town from the Civil War. The victory over the enemies of the Russian people gives him the conviction that a new, better time will dawn overnight. Gleb looks for his comrades from earlier years, but only finds people who are emaciated by their efforts. The cement works where he used to work has been plundered and abandoned. With great effort, Gleb and his comrades try to get the plant up and running again. The struggle seems to begin anew... It is the time after the victory of the “Great October Socialist Revolution“ and the time of building a new society.

1929: Marie Lehning, a farm worker from Warmsdorf on the Baltic Sea, falls in love with the fisherman's son Mingo. Both complete an apprenticeship in Lübeck. Marie wants to become a seamstress, Mingo a carpenter. After their first night of love, they swear eternal fidelity. But Marie has to return to the village, her mother is ill and her siblings are unprovided for. She starts working as a maid on a farm. Unexpectedly, she meets the young Kurt Meier from Berlin, whom she knows from before.

The blind psychologist Tom Leschek and the therapist Jessica van der Laan are after their first successful mission, a team that is again requested when a suicide wants to plunge from a skyscraper. The young woman was held captive for months in a basement prison by arms dealer Hübner as a slave. Tom tries to convince the desperate not to jump. When she flees again and shoots Hübner, she takes Tom hostage.

The water sports fans of a cooperative on the coast finally want to acquire a seaworthy sailing ship. But at the board they encounter deaf ears. Only the chief accountant Irma shows interest in sailing and especially the leisure captain named Ali. Then a minister surprisingly his visit. Irma devises a plan to support the sailors. In order to vote the Minister benevolently, flights, a company sports community should be launched. The founding of a sailing section would be just right. But unfortunately, the Chairman Scheffel continues to be cross. He even wants to use the storage space of the sailors. Only when the minister finds pleasure in the spontaneously organised sailing trip for him, movement comes into the affair.

A series of rapes causes a stir in a German university town. A special commission led by senior public prosecutor Schildt and detective Gawilek investigates. After months of surveillance, everything points to a chaplain as the masked perpetrator, known as "Zorro". But the investigators were wrong, because "Zorro" strikes again when the chaplain is in custody. This time, charges were also filed. But not against "unknown", but against the son of the senior public prosecutor...

A young engineer is sent to post-WWII Berlin to help the Americans in spying on the Russians. In a time and place where discretion is still a man’s best friend, he falls in love with a mysterious woman who will take him on the dark side of evil.