That's No Lady, That's My Spy - S6-E17
Other mistake: The Kommandant's building and the barracks appear to be only twenty to twenty-five feet apart, showing that this scene of Roll Call is in the studio. Otherwise, the outdoor shots are at the studio back lot.
Answer: It's a solitary cell. Steve McQueen, star of 'The Great Escape' is known as the 'Cooler King'.