But he has some problems, because he's missing something important.
The trio goes on a class trip to Kitten Rock, where they visit a 16th century the Germans confiscated all the valuables but did not manage to take them away.
The trio manages to locate that forgotten basement and they find the treasure.
In it, they find many gold valuables but also an old book, with some calculations in it.
The friends assume that it is an old account book so they leave it.
At the end of this chapter the treasure lands in a comes to her house! He gives Grandma Lucy the ring he found in the treasure box. Net and his parents are alone at home also until Nika visits them.
After the supper, Net and Nika go out on the terrace, and Net gives her a ring as a Christmas present.
Chapter 7 - The trio goes on a class trip for a week to the .
One day, the three friends realize that they are being followed by no one else than... Meanwhile Nika gets jealous of Aurelia, the prettiest girl from the class.
When Aurelia and Net go skiing together, Nika is furious and tries to follow them, even though she doesn't know how to ski. Felix and Net go out to search for her, but instead of her they find a troop of soldiers and and that she lives alone, since both her parents died.
This book was chosen as the book of 2005 by the Polish Literature Institute "i"Bb Y.
On the inside of the front and back cover, there are drawings representing situations or objects which appear throughout the book.
Plot summary "A fantastic and hilarious story about thirteen-year-olds, not only for teenagers!