In an ordinary looking apartment, a father and daughter play a game of hide-and-seek. While searching for his daughter, she is nowhere to be found... Later, a video is posted which shows the girl holding a sign with a mysterious set of numbers. But what do they mean? She’s the first of several children who disappear without a trace in a small industrial town.

Young detectives Varta Naumova and Maksim Shumov take on the complex case and… their own demons. Varta is a distant person and extremely protective of her personal space, while Maksim comes across as an easy-going sociable guy. Both have experienced trauma in their lives, and this case touches them on a deeper level. They become personally vested in finding the children and apprehending the kidnapper as they face their respective pasts.

The series is built in the form of saga and depicts the turbulent periods of the beginning of the 20th century through the eyes of ordinary people: the First World War, the revolution, the emergence of Soviet regime. Each of the characters faced the changes in their own way through their concept of truth. However, all of them shared fundamental desire to live, love and find their own place in the new era.