The world-famous expert Drongo is back at work. This time, high-ranking officials from the FSB convincingly ask the investigator to help colleagues in Serbia. There, the local prosecutor’s office is struggling with a mysterious murder of the country’s deputy prime minister, Predrag Baštic. He was strangled in his own mansion during a very important meeting of representatives from the governments of all the Balkan republics. A guard has been arrested on suspicion of the killing, but it’s unlikely to be his doing. Drongo finds that on the day of the murder there were four people in the mansion who should not have been at that secret meeting—and one of them is Baštic’s son…