A message from London arrives to say that an all-out air raid is on its way to bomb General Strommberger's Third Panzer Division at the Mount Hoffenstein Pass just outside Hammelburg. But the winter weather is getting worse (Schultz and then Klink catch bad colds from it), and Hogan realises this will cancel the raid. So it is up to him and his men to find another way to destroy the division.
Meanwhile, Klink wants Hogan and Co to volunteer to rescue a snow-bound truck. Hogan refuses because of the winter conditions. But then Strommberger arrives. He wants volunteers to clear the road for his Panzers. Hogan and Co are listening on the coffee pot. Realising that this is their ticket to wiping out the division, they volunteer. But they lose their explosives thanks to a difficult guard and must come up with another plan.
Schultz lets them stay in the Hofbrau until their equipment arrives. There is a sign outside saying "dancing every night" and the musical instruments are inside. Klink arrives with news that they will not be shovelling snow because snowploughs have arrived; this stymies Hogan's plan to do a deliberately poor job of clearing the road for the Panzers. In order to stay on in town, Hogan and Co send the snow from the Hofbrau roof falling onto Klink's head to make him think his cold is getting worse and stay in town until it is better.
Hogan and Co stay on in the Hofbrau, but cannot come up with a conceivable plan. They are further frustrated when Strommberger orders them to be chained together. However, Strommberger also says he had to remove his men's guns because there have been warnings of impending avalanches in the Hoffenstein Pass, and the slightest noise could trigger one. So Hogan and Co start playing the instruments as loudly as they can to trigger an avalanche, but they fail. Worse, Strommberger guesses what they were up to and orders them to be returned to camp.
Then, Klink, who is now out of his sick bed, gives a sneeze. His sneeze not only triggers the avalanche but sends more snow from the Hofbrau's roof onto Strommberger's head. Now Strommberger catches a cold as well.
Back in camp, Klink and Schultz still have their colds. Klink is affronted at the idea that his sneeze caused the avalanche and says that it is impossible. Then he sneezes again, and his sneeze causes snow from the barracks roof to fall on his head.