Armando Iannucci was adamant he wanted to make 'The Death of Stalin' feel as "real as possible" even though it is a funny film.
The 53-year-old filmmaker is known for his satirical comedies, including 'The Thick of It', and Iannucci said he wanted his latest movie - which is based around the death of the Soviet Union dictator Joseph Stalin - to show how people lived through Joseph Stalin's reign despite it being a comedy.
Speaking to The Daily Telegraph newspaper, Iannucci said: "I wanted them to change and people's perceptions of them to change over the course of the film. And although it was a comedy, it was very important for me to make it feel as real as possible. I went to Stalin's old dacha outside Moscow and to the Kremlin and I talked to people who lived through the purges.
"I remember one old man telling me that the trick was to always go to bed wearing as many layers of clothing as possible.
"That way if the police came for you in the middle of the night, at least you would be reasonably warm."
'The Death of Stalin' focuses on the communist dictator as he lives out his final days and the chaos that erupts in the nation in the wake of his death.
The film is an adaptation of a graphic novel of the same name and stars Jason Isaacs, Steve Buscemi, Olga Kurylenko, Jeffrey Tambor and Monty Python legend Michael Palin.
But Iannucci recalled he told the cast that despite the film being a satirical comedy, they "must always be respectful" to the horrific realities for people who lived under Stalin's regime.
He said: "I remember saying to everyone at the start, this is comedy, but we must always be very respectful of the fact that millions of people died as a result of Stalin's orders. The comedy really is a nervous comedy of hysteria. Hopefully, the laughter comes from these people's struggles to survive, to do anything to save their own skins and advance their careers."
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