Jonathan Pryce has not slept. Actually maybe he has, he's not sure.
He is fresh off a plane from New York, where he is appearing in a play on Broadway with Dame Eileen Atkins, and is due to fly back to perform again the following day.
It's a trip so whistle-stop it makes you want to lie down for a long winter's nap, but 72-year-old Pryce is taking it in his stride.
"I think I slept on the plane," he says as he strains his recollection with a jovial smile.
"I remember that I had some weird dreams, so I must have slept."
Luckily the play is going well, he says modestly, and he is in the charmed position of scoring warm reviews both on stage and screen.
In fact the reviews for his new film, The Two Popes, have been so good he's been tipped to score his first Oscar nomination.
He plays Cardinal Jorge Mario Bergoglio, now Pope Francis, opposite Sir Anthony Hopkins as Pope Benedict, formerly the German Cardinal Joseph Ratzinger.
The odd couple form an unlikely buddy comedy inside the walls of the Vatican, as Benedict reveals his shocking plans to step aside and tips Bergoglio as his successor, making him the first Jesuit pope and the first from the Southern Hemisphere.
It seems like natural casting to see Pryce in the role - when the Argentinian cardinal ascended to the papacy in 2013, the internet was awash with pictures comparing the two men.
But Pryce didn't quite see it that way.
"I wasn't particularly flattered," he admits.
"He's not what I see in the mirror when I look there but the internet was full of the two images, even to the point where one of my sons called me and said, 'Daddy, are you the pope?'
"It went on from there but I would like to think it wasn't just because I look a bit like him that I got the part! I like to think that 47 years of work isn't wasted."
Those 47 years have included numerous real people, ranging from Cardinal Wolsey in Wolf Hall to Juan Peron in Evita, as well as fictional roles such as the High Sparrow in Game Of Thrones, Sam Lowry in Brazil and James Lingk in Glengarry Glen Ross, but perhaps none have been as intimidating as a living pope.
"I was nervous," he admits. "Of course you want to present someone well.
"I've played a lot of real life characters but most of them have been dead and they can't sue me.
"What's interesting about him is he's a flawed character. He's not this great holier than thou figure, he's very much a man of the people and has a history.
"I had read that he wasn't trusted in Argentina for a while because of his supposed collaboration with the junta and that is talked about in the film.
There was a fully rounded character, and whether he be a living pope or not, it was extremely well written."
That writing was done by Anthony McCarten, who penned The Theory Of Everything, Darkest Hour and Bohemian Rhapsody, and the film was helmed by Brazilian director Fernando Meirelles, best known for his work on City Of God and The Constant Gardener.
"I revere Fernando as a film-maker," Pryce says, "and City Of God has been one of my favourite films for a long time so if the film had been about anything, I would have wanted to do it with him."
The project also gave him the chance to work with Sir Anthony, a fellow Welshman (Pryce is from Holywell and Hopkins is from Port Talbot) and someone he had never teamed up with before.
"The film should be called The Two Welsh Popes," Meirelles jokes later.
"I was nervous about that too," Pryce acknowledges, "I held him in high esteem for years and I didn't know what to expect.
"In retrospect, that played well into the relationship in the film because Bergoglio goes there with some trepidation that he is actually in the presence of the pope. Whether he agrees with Benedict or not, he would revere the position.
"I went into some of the scenes and said afterwards I felt like a teenager. I felt as if I don't know how to act on camera.
"I said, 'I don't know what I'm doing', because I was looking at Tony as a consummate.
"But that actually plays well. Fernando says that we are so unalike in our ways of working that it makes for a good relationship."
Was he reticent to play another religious leader after his Game Of Thrones character met such a sticky end?
"I just know they haven't blown me up in this one!" he says with a raucous laugh.
"I have died a lot recently but I was confident going into this one that I wasn't going to die."
And luckily the reception has been rapturous, at premieres at festivals in Telluride, Toronto and London, much to his relief.
"In this instance, it is gratifying because it's a film where you're worried about what people will think of it.
"Even the title The Two Popes, do you want to go and see two old men talking for two hours?
"So it's wonderful, the response it's had. I think it undercuts people's expectations which is the great thing, and from the early frames of the film it tells you you can relax and you can laugh.
"I've made comedies before where nobody has laughed and with this, there are rushes of laughter.
"Like all good theatre, there is a mix of comedy and drama and tragedy and the comedy lightens or darkens the tragedy and vice versa."
It is not yet known if the pope himself has seen the film and what he might make of it.
Production was obliged to build a replica Sistine Chapel in which to film because the Vatican did not want to participate (they did eventually hand over some footage to be featured).
However, representatives of the Vatican have now viewed the finished project and Meirelles is hopeful others might follow suit.
"We are programming a screening for the Vatican, for the cardinals," the director says.
"I hope it happens inside the Vatican but if not, it will be in the theatre in Rome and we can invite him. I hope he sees it but if he does, he won't tell.
"He will see it secretly in his room and he will never tell."
The Two Popes is in cinemas now and will be available on Netflix from December 20