The next morning, when the coach departs – with Lt. von Eyrick travelling with them – all the travellers except Cornudet and the priest ostentatiously snub Elizabeth, while chatting and gossiping with the Prussian. At Cleresville, after Elizabeth, the priest and von Eyrick leave the coach, Cornudet is overcome by guilt at his previous actions, tells the group off and leaves to seek Elizabeth out. He tries to apologize to her, but she rejects him – even so, she has stirred his patriotism again.
The young priest has taken over from the previous curé who defied the Prussians by refusing to ring the church bell, and he has decided to continue that defiance – the bell will remain silent until the first blow is struck for the freedom of France. The Prussian Captain in charge of the village wants the French to submit to them, and ring the bell themselves ("We do not win," explains Lt. von Eyrick, "unless our opponents ring the bell"), but one of his subordinates has vowed that on his next patrol, he will ring the bell himself. Cornudet hears this, and prepares to protect the bell. That night, when the Prussians approach the church to ring the bell, he shoots and kills a lancer charging toward him on horseback.
Meanwhile, the bored Prussian officers have thrown themselves a party, and have rounded up women from the village to attend. Elizabeth feels she must go, as the Prussians threaten to withhold their business from her aunt's laundry unless she does – and she is assured that "Mademoiselle Fifi" will not be at the party; but, of course, he is. When the lieutenant, drunk, slaps Elizabeth after insulting France and the French, she picks up a knife and stabs and kills him. Both now trying to escape from Prussians who are hunting them, Elizabeth and Cornudet are taken in by the priest, who hides them.
When the Prussians make arrangements with the priest for the funeral of Lt. von Eyrick, they ask that the bell be rung as is customary. The priest agrees, and the Prussians feel that they have won their battle. However, the priest explains later to Elizabeth and Cornudet that the bell can be rung now that the first blow for French freedom has been struck – by a woman.
Prior to directing Mademoiselle Fifi, his first official solo directorial credit, film editor Robert Wise had directed retakes and additional sequences on The Magnificent Ambersons while Orson Welles was in South America, and had replaced director Gunther von Fritch on Val Lewton's The Curse of the Cat People. His work on Cat People convinced Lewton to use him again on Fifi. Wise also directed The Body Snatcher for Lewton in 1945.
Lewton and Wise studied hundreds of period paintings by artists such as Toulouse-Lautrec, Delacroix, Daumier and Detaille, to find the look they wanted. Wise later commented: "Because those were low-budget films, we had to stretch our imagination and get results without too much to work with. How we staged them, how we lit them, how we placed our camera was to get strong, effective results without having the material at hand."
Mademoiselle Fifi was in production from 23 March through late April with the working title of "The Silent Bell". Shooting took 22 days on a budget of $200,000 - a record low amount for an American costume drama in the sound era. Sets left over from RKO's 1939 film The Hunchback of Notre Dame were utilized, but because of the skimpy budget, cardboard sets were also used at some points. The outdoor snow scenes were shot at Big Bear Lake, California.
To improve her figure when filming, the French actress Simone Simon wore false breasts which she called "my eyes." Before each take, she would call out "Bring me my eyes!"
I don't know of any American film which has tried to say as much, as pointedly, about the performance of the middle class in war. There is a gallant, fervent quality about the whole picture, faults and all, which gives it a peculiar kind of life and likeableness, and which signifies that there is one group of men working in Hollywood who have neither lost nor taken care to conceal the purity of their hope and intentions.