Bykov was head of the underground apparatus with which Whittaker Chambers and Alger Hiss were connected.
Bykov graduated from Commanders' Upgrading Training School of Razvedupr of the Red Army Staff in 1929.
As he was fluent in German, Bykov served as an Officer of Soviet Military Intelligence (GRU) from 1920-1941, working in Germany.
In 1935 Bukov left abroad and served as Illegal Rezident of Razvedupr in the United States from 1936 to 1939.
[1] After leaving the United States, he became a Lecturer (agent-operation cycle) of the Higher Special School of the Red Army Staff from July 1939 to September 1940, followed by a post as Senior Teacher of the chair of intelligence from September 1940 to June 1941.