The young medical student Klaus Bach has married the love of his life, Irene, and lives with her and their eternally screaming offspring in a small one-room apartment in his parents' house. So things are tight and everyone's nerves are on edge. What's more, the parents' well-intentioned advice is seriously disrupting the young couple's marital bliss.

Irene and Klaus Bach are happily married. But living closely together with Klaus' parents causes a few problems. Added to this is jealousy of his wife's professional success. She leaves Klaus and the child. With strong support from Täve and Atze, the family tries to bring the "little starlet" back home and reconcile the young couple.

Little Nelli is a clever and cunning child. As her parents are both working, her grandmother has to care for her. But her grandmother is no match to Nelly. Out on the street, Nelli also calls the tune and becomes the kids’ favourite with her brash pranks. But when Nelli enters day nursery, the situation changes completely. Suddenly, Nelli is no longer at the centre of attention and starts to upset the group with her aggressive stubbornness and to revolt against the rules.