John Lithgow turned down playing "ghastly threat" Donald Trump several times

But are his methods more devilish than holy? Of course, 79-year-old Lithgow is no stranger to politics himself. Not only did he play Winston Churchill in The Crown, but in recent years he has been a vehement critic of Donald Trump…

Conclave is a film rooted in the machinations of politics. Was that something that attracted you to it?

I think so! I love the fact that it’s about political behaviour. You don’t see stories of politics told in such an extraordinary setting. It was uncanny how this social organism, just like every other political entity, divided itself into a left and right wing. We all have politics on the brain these days, but we don’t think much about the politics inside the Vatican.

What is your own relationship with religion?

I’m not religious. Both my mother and father were from serious churchgoing families, but it never stuck. Still, I have my own morality and I try to lead a good life. And I’m a great fan of religious art, of Bach’s masses and Mozart’s sacred music. There are also certain things about religious holidays that I find deeply moving.

Cardinal Tremblay is a scheming, contradictory character. Did you base your performance on anyone in particular?

I dove into shady parts of my own nature. To me, the film is about the conflict between faith and ambition. I consider myself a serious artist, but I’m still vulnerable to wanting to make more money in my next job. Right now I’m working in the theatre in London, in a wonderful play called Giant [in which he plays Roald Dahl]. But I’m basically paying to do the job. I head to the theatre every night on a London bus. And yet it’s my most precious job ever. I’m loving it! But you bet the next time I’ll want to make a big splash and get paid lots of money for it.

You wrote satirical poems about Donald Trump during his first term. What do you fear most about his return to office?

I really think that Donald Trump is a ghastly threat to America. His presidency hurt our country. In this past year I’ve worked in Italy, New Zealand, Amsterdam and London. Everywhere they were watching our election and were scared to death.

Would you ever consider playing Trump on screen?

I’ve been asked to do it a few times. I wasn’t interested. I feel the only way to play him is by being an outrageous caricature of him. I also think we need a little distance. Give me a few years!

Do you think there is a limit to satire with a figure like Trump?

No, I think it’s important to satirise him relentlessly. It really gets up his nose. But it’s difficult because it’s hard to change people’s minds in politics these days, and it’s hard to run against demagoguery and deceit, and a lack of conscience or remorse.

You studied acting in London; you’ve played Winston Churchill in The Crown; you appeared on Celebrity Bake Off. Are you an Anglophile at heart?

For sure! I had this curious upbringing. My father produced Shakespeare festivals in Ohio. So I’m this combination of Anglophile and American hayseed! A lot of people think I’m English, but I still have to go to my dialect coach when I play an English role. I have them pounding me about my vowel sounds! When I came to play Churchill, I had terrible doubts. But the cast embraced me. They had more confidence in me than I had in myself.

You turned down the role of Frasier in Cheers. Do you ever think about what might have been?

Sometimes. When it came up, it was my early years in Hollywood, and I’d had two Oscar nominations in two years. There was this chance to play a supporting role on Cheers and my agent and I agreed, "Let’s not think about episodic TV." I can’t help but wonder about the road not travelled. But I have so few regrets. For one thing, I did do 3rd Rock from the Sun for six years, which was a glorious experience.

Were you anxious about being typecast after 3rd Rock?

Yes, but it wasn’t as much of an issue, because I was playing an alien who was trying to be human. It was a built-in antidote to typecasting. And one of the next things I did was the Trinity Killer on Dexter. And that was a deadly serious and terrifying role.

You don’t do as much comedy as you used to. Is that a deliberate decision?

Well, comedy doesn’t really come up! For one thing, I think when you get old, you’re not as funny. I’m sometimes asked if I have any interest in reviving 3rd Rock and I say, "No, that was a young man’s game." Old age has been wonderful for me in the serious roles, because so many of them have cropped up and there’s so little competition! If you last as long as I have, you’re the go-to man…

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Conclave is now showing in UK cinemas.

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