During this period Agranov was put in charge of compiling the lists of intellectuals for the forced exile of leading figures of Russian sciences and culture that were seen as the anti-Soviet element.
When asked why he was so merciless, Agranov responded: "Seventy percent of Petrograd intellectuals were standing by one leg in the camp of our enemies.
At the end of his career he led the Trial of the Twenty One against the Trotskyist Anti-Soviet Military Organization, the "Promparty" and "Working Peasant Party" cases.
[4] Immediately after the assassination of Sergey Kirov in Leningrad on 1 December 1934, Agranov was entrusted with the organization of mass reprisals in the city.
[5] In 1935, he was ordered by Yezhov to track down and liquidate "an undiscovered centre of Trotskyists" in Moscow, as a preparatory step for the Great Purge that Stalin was planning.
In February 1937, he circulated among regional NKVD heads a demand for names of Trotskyists and other oppositionists employed with the state security apparatus.