René agrees to meet Yvette in the broom cupboard at midnight. For the moment, they have a quick cuddle, when Edith walks in on them. For once, she asks Yvette to explain the situation. As she is doing poorly at this, René comes to her aid and says he has had a spasm of the heart and that Yvette caught him, when he was about to fall. When Edith and René have sent Yvette upstairs, Michelle barges in, telling both of them, that she and her girls have waylayed a courier from Berlin, thus obtaining top secret German plans for the defence when the allied invasion begins. She has photographed the plans and have the pictures on microfilm, which she intends to send to England by carrier pigeon. However, first she demands to call London on the radio.
Going up to Fanny's bedroom, they find her and monsieur LeClerc having a row. She has found a note from an old girlfriend of his, thinking he has cheated on her again. He tries to explain, that it is from 1927, but she will not listen to it, not until Edith reads the signature of the note and it turns out, that it is Fanny herself who has written it. When the situation has been settled, Michelle asks monsieur LeClerc to get a homing pigeon from René's henhouse. When he has gone, Michelle, René and Edith contact London on the radio. They tell them about the microfilm and that it will be sent to London by pigeon. London then plays a personal message from Churchill himself, addressed to René. It says "Well done, Ronald".
Later, René, Edith, Michelle, LeClerc and officer Crabtree are standing in the square, about to send the pigeon with the microfilm to England. When Michelle has attached the film to one of its legs, she lets it go, but it keeps returning to them. It appears that LeClerc chose the wrong pigeon and took one, whose home place is in Nouvion. Michelle then has another idea. They will all enter the fishmonger float and specially prepare their carriage with propellers and engines, to paddle over to England in secret.
Colonel Von Strohm and lieutenant Gruber are shown into general Von Klinkerhoffen's office. He informs them that, since to war is going badly for the Germans, certain generals are planning to assassinate Hitler, and he is one of them. He has decided, that they are both going to join him in the assassination attempt. The plan is to send the painting to Hitler and have the frame around it stuffed with explosives. As Hitler examines the painting, the fram will be blown up, killing him. Therefore, somebody will have to be present when the picture is delivered to Hitler. When Gruber points out, that they do not have the painting, the general says they will have a forgery made. He has the picture of Gruber holding the painting and Helga can pose as the Madonna, while monsieur LeClerc paints a forgery.
Monsieur Alfonse shows Michelle, Edith and René in to an old storage magazine, where he keeps the floats from the last time Nouvion won the fishmonger parade. Edith remembers it, but it was a long time ago, since she was then sixteen years old. Michelle suggests René be Neptune and Edith accepts monsieur Alfonse's suggestion to be Venus unadorned and lie in a giant clam shell, that is also part of the float. As she tries lying down in it, it shuts itself on her and the others have a hard time opening it to get her out.
The three German officers watch as monsieur LeClerc paints the forgery and Helga poses for it. She is properly covered, only to uncover herself for a short while, when monsieur LeClerc is to paint the boobies. As it is time for this, Von Strohm and Von Klinkerhoffen do not turn away, but instead, they put on glasses, until Helga asks them to avert their eyes.
Herr Flick decides to try a new plan to find the painting. While Yvette and Mimi are acting as "ladies of the night", they will kidnap them, put on their clothes and, using their keyes, get into the café to search. To this end, they try on some wigs to make them look more convincing.
Meanwhile at Von Klinkerhoffen's office, he makes a simulation of the blowing up of the picture frame, by putting an empty frame in front of a dolly, dressed as Hitler. He and the two other officers are at a safe distance, when he blows the frame up with a radio frame. However, it does not quite work as planned, as part of the ceiling in the room is blown up, but the dolly is unharmed.
In the evening, herrs Flick and Von Smallhausen drive up to Mimi and Yvette in the square and pick them up. They bring them to an empty garage, where they force them to take off their clothes and then let themselves be tied up, all the time thinking it is some sort of game the two Germans want to play. However, they are not so glad when the two Germans leave them tied up in the garage and disappear.
When René and Edith have gone to bed, herrs Flick and Von Smallhausen sneak up to the café, open the front door and go in. They decide to start searching upstairs and go there. However, the clock strikes twelve, so René gets up to join Yvette in the cupboard. As the two Gestapo officers hear somebody coming, they hide, Herr Flick in the cupboard. Thus, René finds him in there, but since it is dark, he cannot see it is not Yvette. Meanwhile, Edith reaches for René's hand in the bed, but as he is not there, she wakes up, wondering where he has gone. As she goes looking for him, she finds him in the cupboard and is at first furious, finding him in the cupboard with a tart. However, when she realises it is Herr Flick, she is more surprised than angry, but still wonders what the two of them were doing in the cupboard. René tries to explain he thought the noise he heard was caused by burglars and went to look for them. Edith finds it somewhat hard to believe, but the next moment, they are interrupted by Herr Flick, who orders Von Smallhausen to come out of hiding and then orders René and Edith to find the painting, or they will be shot. The two Germans then go down the stairs to leave.
Meanwhile, Mimi and Yvette have escaped and, dressed in mechanics' overalls, try to get into the café. As the door is locked, Yvette climbs up to René's and Edith's bedroom window, which she has spotted open, in order to go downstairs and open the door for Mimi. While Edith goes downstairs to have a glass of water, René goes back into the bedroom, only to find Yvette in there. She explains that she has had a terrible night and wants René to hold her. Hoewver, this is out of the question, since Edith may be coming back any moment. Instead, he forces her to hide in the wardrobe. However, as Yvette has already kissed him and covered his face with lipstick, he decides to hide in there too.
When Edith walks into the bedroom, she is surprised not to find René in there. However, as she sees the window wide open, she assumes René has sneaked out that way to meet a secret lover. Angrily, she decides to get dressed and follow him and therefore goes to the wardrobe. She is even more surprised to find both René and Yvette in there and when she demands an explanation, René simply says that he is "not made of explanations" and that "in a marriage there must be some trust", upon which he closes the doors around him and Yvette. For a moment, Edith decides he is right and that she is overreacting. However, when she has "thought things out" for a few seconds, she picks up an axe from under the bed to go hacking the wardrobe. However, she is rather frightened when René and Yvette start making the wardrobe move towards her.