What's inside a visiting German general's briefcase --- the one that's chained to his wrist? The mystery becomes too tempting for Hogan. who not only wants to photograph the case's contents, but then sneak the photos out of Stalag 13 as well!

Hogan must somehow get himself hospitalized so that he can get top-secret information from a wounded British agent who has been posing as a Nazi officer.

When a rocket lands near camp, the heroes don't know how they'll smuggle it out --- until Russian spy Marya comes on the scene.

General Burkhalter's sister Gertrude thinks her dim-witted fiance should be made Klink's assistant, which interferes with Hogan's plan to aid an American general.