Smiley is played by Gary Oldman in the new film, a role Alec Guinness took in the 1979 television adaptation. People will ask, but I wouldn’t for one minute allow myself to compare Guinness with Oldman. Gary has an extraordinary command of himself as an actor. I’m hypnotised by his performance: he steps right outside himself. With Oldman, you share the pain and the danger of life more, the danger of being who he is. It’s a much tougher Smiley, with – here and there, as it is in most of us – a little cruelty.

That’s not in any way to diminish Alec: they’re just different beasts in different products. The original story was adapted for television in seven episodes. The film has to tell the story again with a great deal less sentiment. The ethics and the affections have shifted: it’s sexier, grittier.

Once you’ve lived the inside-out world of espionage, you never shed it. It’s a mentality, a double standard of existence. You probably have it before you enter, which is what makes you attractive – you have a bit of larceny, you have a double way of looking at people, you instinctively manipulate.