Once Sue Hollister receives a lucky penny as a reward, the entire family takes up the fascinating hobby of coin collecting.
Their interest in coins quickly mounts when, on a visit to their cousins, Teddy and Jean, the family car is buffeted by a small tornado.
In the roots of a tree blown down by the twister, Pete finds an old metal box.
In it is a rare Oak Tree shilling and on the coin--the figure of a bird and the letters, t-r-e-a-s-u-r-e Is there a real treasure, and if so, where.