Shortly before the Russo-Japanese War, Reilly appeared in Port Arthur, Manchuria, in the guise of a timber company owner. Here he remained for four years, familiarising himself with political conditions in the Far East and obtaining a degree of personal influence in the ongoing espionage activities in the region. At the time he was still a double agent for the British and the Japanese governments. The Russian-controlled Port Arthur lay under the ever-darkening spectre of a Japanese invasion, and Reilly and his business partner Moisei Akimovich Ginsburg turned the precarious situation to their benefit. By purchasing and reselling enormous amounts of foodstuffs, raw materials, medicine, and coal, they made a small fortune as war profiteers.