Green Acres

The Beeping Rock (5x23)

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A wild story told by an 11-year-old about his recent trip to the moon enthralls Eb and Lisa. Oliver believes none of it, especially when the kid sells Lisa a "moon rock" for $14. But once the rock starts beeping under the moonlight (and when Arnold snorts at it), he suspects he's the subject of a practical joke. Oliver ships it off to NASA for their scientists to examine.