Konstantinos will meet his cousin for the first time in the small village of Zagori, from which his father hails. In Germany, where they live, he is constantly sick, and they hope the change of environment will do him good.
But who is the elderly woman with the tattoo on her hand who sells snails in the surrounding villages? What does her strange name mean? Why does she carry a yellow star with her?
The children learn a new word: Holocaust. They thus discover a side of History they had never heard of before and begin to delve into the life of the elderly woman...

Will they shed light on the mysteries that surround her? Will they complete their secret mission?