Just watched the film and despite it being a comedy it was hard to differentiate between it and reality.

Did he do away with millions through the 5 years plans

No that was Gary Coxall

Who did he play for?

I watched it a few months ago, it's one of these things that really does show what a Dark Comedy is - there's moments that are funny and horrific at the same time - the scene of prisoners being executed in the Gulag, with them suddenly stopping when news of Stalin's death is passed on for example. It never forgets the background to it - the fear of being one wrong word away from being dragged off by the KGB, and it might not even be your word. One of the most chilling things is that while it isn't all true, more of it is true than you might think...

When I Watched the drama surrounding events that lead up to the disaster at Chernobyl, the death of Stalin sprung to mind on how the Communist systems worked, or not in Russia.

I heard a Russian joke that went along these lines.
All the Animals are running out of a Zoo, and the Zoo keeper asks, why are you running? They are shooting all the Gorillas, but your a Lion says the Zookeeper... try telling the KGB that, says the Lion

He’s dead?

Thoughts and respect to his family at this sad time.

RIP.