Series 4

Having been trapped in the POW camp, René is enlisted in the plan to re-dig the tunnel, by getting rid of the dirt. Von Strohm and Geering are playing cricket, though not very well, and Herr Flick and Von Smallhausen are digging their own tunnel into the camp. Monsieur Alphonse arrives at the café to report to Fanny the news that René has been captured, but René and company join in on the British prisoners' plan to escape – though it will free only one man. Meanwhile, Helga reports the situation to Gruber, and together they devise a plan to rescue the Colonel, the Captain and René - involving Gruber dressing as a nun!

Dressed as girls from the Folies Bergère, the entire gang (the staff and the Germans) escape from the prisoner-of-war camp, and completely against plans bring the two British airmen with them. Outside again, the Colonel finds that the Captain is missing; only his glasses are found. Herr Flick and Von Smallhousen intercept a message from London and try to send their own, but René catches on and tosses the radio out of the window, which leaves the Resistance without a means to contact London, until Michelle suggests the radio in Lieutenant Gruber's little tank.

Since Maria's disappearance, the café needs another waitress, but René and Edith have somewhat different ideas about who should fill the position, but finally Michelle of the Resistance brings tiny Mimi from another cell to be René's bodyguard. In the meantime, General Von Klinkerhoffen gives the Colonel a new assistant - Italian liaison Captain Bertorelli.

The Gestapo suspects that the Colonel and the General are in on a plot to assassinate Hitler, so Herr Flick goes undercover as Private Irma Von Kinkenrotten and plants a somewhat bizarre daffodil-shaped microphone in the Colonel's office, where Gruber and Von Strohm are making plans to get rid of Bertorelli in some way. Meanwhile, as Edith prepares for her wedding, René and company must get the aerial for their new radio above the jamming signal of Herr Flick, so they disguise Mimi as a small nun to obtain a box kite which they fly to contact London and request plastic explosives to blow up the safe in the General's chateau to get the British Invasion plans.

There are still no batteries for the wireless radio underneath the bed of René's mother-in-law, so Michelle's newest harebrained scheme is to have René and Yvette powering it with the generator from a bicycle until the stolen batteries from a German miniature submarine are delivered. The Lieutenant has finished copying the paintings (The Fallen Madonna and the Van Gogh) and delivers them as sausages. Numerous other sausages also arrive: real ones from Captain Bertorelli, submarine batteries from Leclerc, and explosives from Officer Crabtree, and soon they're all mixed up in the German officers' trousers!

The Germans arrest René, and the Colonel demands an explanation for the knockwursts with explosives in them. After a small lie, René is sent home with around a dozen knockwursts to hang in his kitchen. Meanwhile, the British have sent a spy camera with which the Resistance should be able to photograph the plans for the German invasion of Great Britain, but the camera landed in the vineyard of Monsieur Alphonse, and since the Germans commandeered the vineyard, the Resistance cannot go and look for the camera. This problem is solved when the General orders every peasant in Nouvion to work on the vineyard, which also leaves room for some assassination attempts on the General's life.