The killer maniac, whose arrest operation is being carried out by a special Los Angeles police team, takes a certain man named Thorne hostage. The operation is successful, the hostage is freed, but in Thorne's bag the police found a pistol and a notebook with incomprehensible notes. This is the beginning of a mystery that will have to be revealed by John Barron, a policeman who finds himself on the run and forced to even change his name. Who could have known that the American trace would stretch across Europe and manifest itself in distant Russia. And the case that Barron is investigating involves the descendants of the Romanov royal family, who are waging a fierce battle for the Russian throne.