Vlasik's military career had an early beginning. In March 1915, he was called into the army and by the beginning of the October Revolution was already appointed to the rank of corporal. In November 1917, he began serving in the Moscow militia. In September 1919, he was transferred to the Cheka. By January 1926, he had become the senior representative of the Operative branch of OGPU. Furthermore, Vlasik held supervising posts in the operations section, which included the protection of the heads of the party and government. For many years, Vlasik was chief of Stalin's personal protective service in Kremlin, beginning in 1931. He also became, in essence, a member of the family. After the death of Stalin’s wife, Nadezhda Alliluyeva, he was also the tutor of Stalin’s children and practically carried out the functions of a major-domo. In the memoirs of Stalin’s daughter, Svetlana Allilueva, she characterizes Vlasik as an "illiterate, silly, rough and extremely impudent despot". She said he was so corrupted with authority that "he began to dictate to art workers and arts, tastes of comrade Stalin", and "...figures listened and followed his counsels. Any celebratory concert at the Bolshoi Theatre or George Hall did not take place without the sanction of Vlasik".
Arrest
On December 15, 1952, Vlasik was removed from his position and soon arrested on charges in connection with the Doctors' plot. Immediately after Stalin's death, all of the accused doctors were released and charges against them dropped. However Vlasik was not released and the charges against him were changed to abuse of power and embezzlement. In 1955 he was stripped of his General rank and all medals and exiled for ten years to Krasnoyarsk. In accordance with an earlier amnesty, his sentence was reduced to five years. In 1956, Vlasik was pardoned but his rank was not restored. In 2000, 33 years after his death, his sentence was annulled and he was completely exonerated. In his memoirs Vlasik wrote, "I was severely hurt by Stalin. For 25 years of doing an irreproachable job, receiving nothing but encouragement and awards, I was excluded from the Party and flung into prison. For my boundless fidelity he gave me into the charge of my enemies. But never, for any minute of the condition I was in, to whatever mockeries I was exposed while in prison, had I in my soul any malice against Stalin". According to his wife, Vlasik was convinced that Lavrentiy Beria "helped" Stalin die.