After Maria is sent to Lieutenant Gruber with the sausage containing the real painting of the Fallen Madonna for copying, she is caught by General von Klinckerhofen, who places the sausage in his wardrobe and helds Maria hostage until his lawn mover engine is returned by the Resistance. Herr Flick, the Colonel and the Captain, and René hears about this and decides to go to the chateau through the secret passages and steal the sausage from under the General's nose, using Helga, Yvette and Lieutenant Gruber as erotical bait.

While the Captain is sitting in the café, herr Flick from the Gestapo is listening when René is talking to London on the wireless. He soon cracks the code surrounding the message with the plan to dig a tunnel from the mortuary to hide the British airmen. But it's soon apparent that the two airmen and Monsieur Alphonse need help with the digging, and the café staff are called in, leaving Madame Fanny and Leclerc in the café. But the Colonel and the Captain follow René, discover the tunnel, and are captured in the prisoner of war camp.

After the plot to get the two British airmen out failed, a frustrated René returns to the painting of the Fallen Madonna. He hides it behind an ugly painting in his café which is immediately recognized by General von Klinkerhoffen as a Van Gogh and requisitioned for his office in the chateau. He also requistions the two new maids in Café René – or as they are better known: the two British airmen in disguise. Realizing that the two airmen will be recognized right away, Michelle of the Resistance comes up with another hairbrained scheme of digging a tunnel from Monsieur Alphonse's morgue into the prisoner of war camp and smuggling in the two airmen into the camp.

After the Colonel makes René promise not to hang out with the Resistance anymore, Herr Flick's sausage (containing the forgery of the Fallen Madonna) is kidnapped by the Communist Resistance. The Colonel and the Captain are anxious that it doesn't come out that they have switched the paintings, and order René to come up with the ransom, which Edith gets from Monsieur Alphonse. The ransom is to be left by René and his staff, dressed as German soldiers. But the whole thing is watched by German soldiers dressed as French policemen, the Gestapo dressed as French Resistance girls, and the Colonel and the Captain dressed as trees. And of course, Lieutenant Gruber stumbles upon the meeting, and his dog can't help but chase the sausage.

The sausage containing the painting of the Fallen Madonna, which was taken by Lieutenant Gruber's dog, is minced by the Lieutenant – but fortunately he discovers it first and saves it. At the same time, the missing knockwurst means that Monsieur Alphonse cannot get back the money which he leant to pay the ransom of the kidnapped sausage. The Resistance pays him back with Monsieur Leclerc's badly forged money. But after everything seems to be getting back to normal, the sausage is sent to Lieutenant Gruber to make another copy. Also, Michelle's latest plan to get the British airmen back is by an old plane with the motor from general von Klinkerhoffen's lawn mower.

With René again in the possession of the sausage containing the painting of the Fallen Madonna, the attention turns to getting the two British airmen out of France. Michelle proposes a steam engine tour through Nouvion. Michelle's newest hairbrained scheme of getting the airmen out will of course need 80 meters of suspenders, and it's René's job to get them from every Frenchman in Nouvion. Herr Flick and Helga arrive in his staff car to spy on the show.