Scott, Jack, Emily and Drift the dog are stunned to discover a secret room in Stone Cottage. The friends investigate in the 13th adventure of the series.

When Boomerang the cat disappears into a tiny gap behind the fireplace at Stone Cottage, Scott, Jack and Emily are amazed to discover a secret room that Aunt Kate never knew existed! But what was the room created for? Inside is very little other than an enormous old chest which Jack is convinced must be full of treasure, but what secrets will be revealed when the friends finally manage to open the box?