Tanel are visiting their grandparents for the summer, which is bound to be an
ordinary one. Even though they have nothing against spending their time just
with each other, going swimming and fishing, taking care of the garden and
picking berries, they are still happy when a new boy, Marten, moves into the
village. Yet, all of a sudden, the three children who have barely become
friends are drawn into a mind-boggling adventure that involves ghosts,
bootleggers, a mysterious vacationer, fake archaeologists, heritage protection
specialists and a lost treasure.