Sanne Moder, an 18-years-old girl with a ready tongue, is sent by her father to Frankfurt, to stay with her aunt. Working for the domineering and bad-tempered woman in her stationer's shop, Sanne falls in love with her son, Franz. Together with his friend, Paul, the three open a tobacconist's of their own.
On hearing about the shop and the girl's plan to marry Franz, the aunt denounces Sanne to the Gestapo.
Although Sanne is acquitted she leaves her aunt and Franz and moves in with her brother, Algin, who is writer, and his wife Liska.
Deeply affected by the death of a six-year-old girl and the tragic fate of Jewish friends, Sanne's instinctive aversion to the Nazis hardens into conscious resistance.
At a party at her brother's house she sees Franz again. He is on the run. He has killed an informer who denounced him and Paul to the Gestapo for anti-government activities. While the party reaches a dramatic climax - Algin's friend, Heini, a journalist, shoots himself - Sanne and Franz prepare to escape from Germany.
In the dead of night they catch the train to Rotterdam.