The adventures of three friends from East Germany on the Black Sea.

Mauritius Halbermann, nicknamed "Mauts", works as an advertising manager for Gravo-Druck, a state-owned print company. Mauts, a man obsessed with his work, incessantly percolates with marvelous ideas - and now that he has once again come up with another brilliant idea, he naturally wants to present his proposal to his boss. As it happens, his supervisor along with his entire family and some of Mauts's colleagues - including Lore who Mauts secretly fancies - have gone on a holiday trip.

Ev and Peter fall in love at first sight. Peter studies dentistry in Leipzig and is eager to work in the country. There is an unfilled dentist vacancy in his home village. Ev, on the other hand, is drawn to the city. Being a commercial artist, she sees no chance to find a job in the country. This conflict becomes the first real test for their relationship.

Co-pilot Horst Schubert is a braggart and a true Don Juan. Thus, he tells young Ilse that he is in fact an "aircraft commander". This assertion brings about an embarrassing situation, for he suddenly meets her onboard his new work place, an IL-14 charter plane where Ilse acts as a stewardess. It gets worse, however: During a stop in Varna the police appear because Horst’s former lover Madelon has vanished. At home, meanwhile, his landlady has her hands full with her lodger’s current and former playmates. Ilse decides to put an end to this mixup and since the dull captain of the plane, Richard, makes no move to confront his co-pilot about his unstable private life, the smart stewardess appeals to the rest of the crew to help her teach Horst a few lessons in love.

At the end of the 1950s, the production of optics in the German Democratic Republic has reached top quality and instigates interest in the West. When national demand rises strongly and at the same time the export to South America heavily decreases, the Volkspolizei - the GDR police force - starts to look into the case. Two seemingly unrelated cases are the starting point for the investigation by second lieutenant Schellenberg of the department for optics racketeering: An old woman who was arrested in the Berlin city railway for trying to smuggle a pair of binoculars to West Berlin, and a dead person in an area of allotments who was involved in obscure dealings with optical devices.