At Stalag 13, a German prisoner-of-war camp, Colonel Robert Hogan and his fellow cohorts are a subversive group with many hidden talents. However, a spy has been planted amongst the men by the Germans. And when he learns of the gang's subversive operations, "Hogan's Heroes" must act fast to discredit him.

To prevent Colonel Klink from being transferred to the Russian front, Hogan and his men attempt to convince a visiting Inspector General that the Colonel is a cold, heartless disciplinarian. But their plan backfires when, as a result, Klink is promoted to a post in Berlin!

Hogan manages to free four underground leaders from the Germans and smuggles the quartet into Stalag 13. But a plan to spirit the men off to freedom in England suddenly looks hopeless when a leaky pipe fills the gang's emergency tunnel with water!

The bumbling Sergent Schultz has unwittingly been conned into making a trip to Heidelberg as courier for the underground, but after upsetting Colonel Klink, the sergeant is ordered to remain grounded at the camp. How will Hogan and the gang win him a new weekend pass?

Hogan is ordered to capture an "escaped" Corporal Louis LeBeau --- but in a manner that will ensure LeBeau's completion of an espionage caper.