Ten-year-old Susan and her best friend Hiram think that Susan's birthday party will provide the only spark of excitement during the long summer months ahead. But when Uncle John suddenly takes an unusual interest in aging Great-aunt Libby's farm, the once-quiet Midwestern town starts buzzing with speculation. Susan and hi find themselves the bearers of an important clue to the mystery when a visit to the farm produces some curious discoveries.
Excitement grows when Great-aunt Libby's valuable antique silver egg disappears. Susan plays sleuth, and when the egg is found, it reveals a wonderful surprise answer to the mystery.