The Oligarch's Safe

They say that if banker and oligarch Prokopov sneezes, the entire financial system of the country will start coughing. You can imagine how well protected this man is. But something incredible happened: the robber got into not only his residence, but also the holy of holies—the safe room where Prokopov kept a collection of precious stones. Of course, they shot him at close range. But famous detectives—Colonels Gurov and Kryachko—are the most alarmed by this. A lone man couldn’t have done it…