The plot is fictional; however, it does reflect actual events to a significant degree. In parallel, it narrates the personal stories of the seven victims, including the murderer. In particular focus is the story of the Bulgarian bus driver of Muslim origin who died in the attack, while emphasis has also been placed on the dramatic clash between a photographer and the lead investigator in the case. While working on the script, co-writers Shishmanova and Berlin-based scriptwriter Milena Petrova made use of interviews with the victims’ loved ones, the surviving passengers and the individuals involved in the investigation, as well as records of interrogations of witnesses, photos, and footage from the investigative analysis of the planning and execution of the attack.