René is in the backroom, packing a few belongings in a suitcase, since he has decided to elope to Switzerland with Yvette. She enters the room and puts some of her belongings in the suitcase. Secondly, she asks about the gold and, thinking that René is hiding it on his person, she starts tickling him. As she is doing so, Edith walks in on them and René tells her that Yvette is looking for the key to the wine cellar, after which she is sent into the kitchen with some dirty dishes. Edith says she does not trust Yvette and that she wants her to leave. René can truthfully say she will be gone the same day. Edith then also says she wants to know where the gold is hidden, but before René is forced to tell her, Mimi enters the backroom, announcing that colonel Von Strohm has arrived, with two soldiers and general Von Klinkerhoffen, wanting to talk to René. They quickly go outside, when a German soldier barges in and forces them.
Lieutenant Gruber, who has also come along, informs René that they have arrived to search the café for the Enigma machine. If it fell into the wrong hands, particularly those of the Gestapo, all the German army's secrets could be revealed. The general informs everybody that anyone trying to leave Nouvion will be shot and leaves the café. The Germans then start searching the café and one of the soldiers finds René's suitcase. Gruber looks through it, but being the way he is, he is not at all surprised to find a woman's undergarments (Yvette's) in it, though René assures them that it contains only "his personal belongings". Gruber also goes upstairs to search Fanny's bedroom. He does not find the Enigma machine, but when looking through her bed, he finds a book entitled "Wheel Chair Jujitsu".
Later, when the colonel and the lieutenant are having a glass of wine, a girl wants to enter the café. Monsieur LeClerc says she is "one of René's ex-waitresses" and when she is finally let in, on the colonel's orders, René does not recognise her, but she is looking pregnant. When she has revealed herself to be Michelle, she and René go into the backroom, where she delivers the Enigma machine. It was supposed to be delivered to two Englishmen, who had come along with the midget submarine, but when they landed in France, the went in to a restaurant and got drunk, after which they were arrested and revealed as British. Now, René is to put it in a small wine keg, which he will drop down the hole in the square, made by the exploding puddings. They will then go into the main drain, from where it will be flushed to the outlet of the sewer (when everyone in Nouvion, at a prearranged time, will flush their toilets), where the submarine is waiting. The operation will take place the next morning, when the RAF will create a diversion, by bombing the German headquarters. Michelle also picks up a note with a message, which the British airmen are to deliver to their commanding officer at once. René calls them out of the cupboard, where they are hiding and Michelle gives them the note, after which she leaves.
The next morning, monsieur LeClerc has placed the Enigma machine suitcase in the wine barrel - and drunk the wine to get rid of it. Therefore, he is rather drunk and falls asleep in the café. Monsieur Alfonse also shows up, with a blueprint of the town drains. The café gang (all except monsieur LeClerc) study the blueprint, but monsieur Alfonse is overwhelmed to feel Edith embracing him and Yvette and Mimi showing their nightwear.
When they have all got dressed, Yvette, René and Alfonse go out into the town square and drop the barrel in the hole, which leads down into the sewers. Somebody has to "push it to the junction". Mimi has volunteered to do this and also comes out, dressed in a dyving suit. They put a rope around her and lower her into the hole, as Edith joins them. When they try to pull her back up, the rope slips off her. They try to attach it to her again and pull a second time, but this time, they manage to pull the dyving suit off her instead. René manages to grab her feet and pull her up, but as she is not wearing anything, monsieur Alfonse once more becomes overwhelmed by this sight and his dicky ticker sets in.
When they are back in the café, just waiting for everybody to flush their toilets, officer Crabtree enters the café and tells them that the RAF has dropped a bomb on the water works, so there is no water flowing in the drains. Edith comes up with a plan to make the barrel float away - to pour wine down the drains. This plan works and the barrel is soon floting away through the sewers. When they are celebrating this, Yvette asks René into the backroom, where she tells him what kind of underwear she had put in the suitcase. She is worried that Edith might find it and René picks up his suitcase to check it. Doing so, they both find that monsieur LeClerc has put the wrong suitcase in the barrel, meaning René's case with his clothes and Yvette's underwear is floating away to be picked up by the British, while they still have the Enigma machine. The next moment, when Michelle arrives to all congratulate them on a job well done, René and Yvette cannot make themselves reveal the mix-up, but keep quiet about it.
- Note: In this episode, Richard Gibson (Otto Flick), Kim Hartman (Helga), John Louis Mansi (Von Smallhausen) and Gavin Richards (Captain Bertorelli) are credited without appearing.