This is an obscure one. I saw it many years ago when I was in high school, so it was available in the late 60s.
The scene was a kitchen. The plot involved a husband and wife suddenly being surrounded by the aspects of a spy thriller – gunshots, mysterious phone calls, etc.
About halfway through, and man walks into the kitchen and sits, putting his feet up on the kitchen table. He reads a newspaper.
Neither the husband and wife pay the slightest attention to him. He continues to read until there’s a gunshot or some other thrilling moment.
Then, the man puts away his newspaper and says words to the effect, "That’s fine. But at the next rehearsal, I want . . . " The joke being that he is the director of a play watching the runthrough.
Any ideas?