Gwenda is an ardent writer, editor, and hiker. A tiff at home sends her off to her favorite retreat nearby - an immense mountain that dominates the landscape and towers above the city and the bay it sits astride. There are still many unchartered parts of the mountain with untrammeled woods, creeks, and ravines. Gwenda heads for an area where, on her last hike, she saw a running stream in the distance which seemed to emanate from a pile of rocks. Curiosity leads her to two startling finds on the bank of the small creek. She shares her findings with the park rangers and an antique arts dealer trying to discover more information. She also involves local resources and the Internet to research the background of one particular clothing object which clearly hails from a distant past. She learns about a community of specialized workers living in the city nearly a century ago.

A mystery from those times is suddenly revealing clues in the present time. The police inevitably become involved but are not enthusiastic problem solvers. As a columnist for the local newspaper, Gwenda reveals information about her finds in suspenseful instalments to readers. Readers respond trying to help solve the puzzle she presents. In the end, an unusual exchange with one particular avid reader leads to a meeting which helps determine the solution to the mystery on the mountain.