A jealous husband hires a private detective to check on the movements of his wife. The husband wants more than written report: he wants movies of his wife's activities.
A week later, the detective returns with a reel of film. They sit down together and proceed to watch it. Although the quality is less than professional, the man sees his wife meeting another man!
He sees the two of them laughing in the park. He sees them enjoying themselves at an outdoor cafe. He sees them dancing in a dimly lit nightclub. He sees a dozen activities shared by both the man and woman with utter glee.
"I just can't believe this," the distraught husband said.
The detective says, "What's not to believe? It's right up there on the screen!"
The husband replied, "I just can't believe that my wife could be so much fun!"