A secret military document is mistakenly hidden in Colonel Klink's topcoat at a party, and a desperate Hogan must nab the document because of both its value to the allies and because Klink will be charged with treason and replaced at Stalag 13 if it is discovered in his possession.

Klink becomes convinced that he is marked for assassination by a mysterious "Mr. X" after a series of close calls at the stalag. Could Hogan be behind the threats? Yes... but it's all part of a plan to masquerade as Klink in order to help a valuable underground agent escape from the camp!

When Sergeant Carter constructs an amazingly complicated rabbit trap, a suspicious Colonel Klink comes to believe that the contraption is a secret electronic spying device.

The clumsy and annoying Colonel Crittendon inadvertently messes up Hogan's plans to destroy a German ball-bearing plant.