Arkadiy Koshko was one of the most famous detectives of the Russian Empire. Starting his career as a simple inspector in Riga, he solved eight crimes in his first year, which was considered a significant achievement. Koshko was known for his creative approach to investigations. To catch card sharks, he trained with former con artists and, posing as a gambler, infiltrated casinos. After defeating the cheats, he would suggest they play against their leader, who would then be arrested. In his work, he used makeup, false mustaches, and various costumes, often catching criminals 'red-handed.'

In 1908, Koshko was transferred to Moscow, where he solved a high-profile case of jewel theft from the Assumption Cathedral in the Kremlin. After examining the crime scene, he suspected that the thief had not yet left the cathedral. The operatives thoroughly searched the area but found nothing. Koshko then ordered the cathedral to be surrounded and to wait. Three days later, the thief emerged from the iconostasis, having survived on prosphora all this time.

Koshko's career included true adventurous investigations, such as the capture of the killer gang led by Vasya Belous. The criminal became so brazen that he sent letters to the police mocking their attempts to catch him. Koshko eventually found Vasya, who was executed.

Arkadiy Frantsevich not only conducted investigations but also improved the law enforcement system. Thanks to his efforts, fingerprinting, photography, and anthropometry began to be actively used. He changed the methodology of raids, making them unexpected even for the police. After the revolution, Koshko emigrated to France, where he was offered a job at Scotland Yard, but he declined.