Only she knows who's the murderer

The Photographer is an elusive serial killer operating in modern-day Moscow. He leaves numbered tiles at the scenes of his crimes, similar to those placed at crime scenes by forensic teams. The investigation points to the old Red Army barracks in Legnica, and to events dating back to the 1970s. One of the people involved in the investigation is Natasha - the only person to have survived an encounter with The Photographer.