Even in the 1980s, the UK Left was certain that Reagan was going to bring about a nuclear war.
There are other bits of hysteria that never come up in discussions of “red scare paranoia”. The Left has their own kooky conspiracy phobias.
https://en.wikipedia.org/wiki/A_Very_British_Coup
(Written in 1981, adapted for the telly in 1988).
The most blatant example of this was the movie "Threads."
I remember watching some of that. My favorite scene was when, during his supposed ‘resignation’ speech, he reveals the attempted blackmail and admits his long-ago affair. The people who were trying to push him out are sitting incredulous as he speaks, and the exchange between two of them is priceless:
“He’s telling the truth!”
“He can’t do that...he’s the Prime Minister!”
As for the original subject...the movie has a very ambiguous ending. After the deadline passes, and the US and USSR have detonated the “fix it” bombs, the church bells start ringing all over London. The thing is....you don’t know if it’s in celebration that things got fixed and mankind is saved, or in a last call to worship because it didn’t work. The audience is never told.