Well, Lavrenti Beria did, according to the memoirs of Vyacheslav Molotov, say that he did Stalin in and saved them all.
What was being referred to cannot be ascertained as they guarded their speech at that time.
It could have meant that Beria delayed treatment to Stalin, or it could have meant that he actualy did poison the old jerk.
Stalin’s funeral was an interesting thing to read about.
Beria was stated to be triumphant and left for the Kremlin.
Someone stated that Beria was off to seize power, which began a mad dash for their cars from the funeral..
Over 500 people were crushed to their death trying to view Stalin's body as it lied in State. If you ever saw the movie "The Inner Circle" they show how crazy it was as masses of people rushed to try to view the body.