The beginning of the story takes place in one of the rich neighborhoods in the city of Lazarevac in the early 1980s, and describes the growing up of the sisters in a luxurious house with an insensitive mother and an attentive father. One summer afternoon in the park, a terrifying event will change their lives forever. While their caring nanny took her eyes off the swing just for a moment, evil took matters into its own hands and changed their fate. Throughout the book, the main character Masha struggles heroically to find out where her sister disappeared on that fateful afternoon, and encounters terrible experiences trying to find any details. The story vividly explains the devotion and strength of love from the point of view of one sister who selflessly gives her all and walks with open eyes towards her worst nightmare, hoping to see her again.