Drawing on a number of previously unpublished sources, this article uncovers the complex and non-linear connection between two high-profile events of the early twentieth century that occurred eleven years apart: the explosion at the Bolshaya Severnaya Hotel in April 1904 during preparations for an assassination attempt against the Minister of the Interior, Vyacheslav von Plehve, and the execution of Colonel Sergei N. Myasoedov in April 1915 after his conviction for espionage on behalf of Germany. The link between these two tragic episodes was provided by Mikhail I. Trusevich, then Assistant Prosecutor of the St. Petersburg Judicial Chamber and later Director of the Police Department, who was assigned to investigate the 1904 explosion, as well as by the fur coat belonging to the man killed in the blast, which became one of the key pieces of physical evidence in the case. The principal objective of the investigation was to establish the identity of the deceased. Through investigative work carried out in Montreux, Switzerland, and at the border station of Verzhbolovo, Trusevich succeeded in locating a relative who had accompanied the victim while making purchases. This ultimately led to the identification of the deceased as the Socialist Revolutionary Alexei D. Pokotilov. The negligent handling of this crucial piece of evidence by Myasoedov, who at the time was responsible for gendarmerie supervision at Verzhbolovo, occurred despite repeated instructions from his superiors to provide full assistance to Trusevich. The unfavorable impression of Myasoedov’s professionalism that Trusevich formed during the investigation had lasting consequences for the gendarmerie officer’s career. It deprived him of corporate support within the service and ultimately made him an easy target for subsequent political intrigue.