Who is Hortensia Malin and where did she disappear? What does the abbreviation mean to AA? Who is protected by the teacher Krkavec? Who lives in the Great White House? What secret does the treasure guard guard? What is on the bottom of the well? What are the sacred artifacts? Who is in danger? How to save books? All these mysteries must be solved by three eleven siblings Linda, Anna and Hugo. Unfortunately they have very little time and the enemy has a big lead