Frank Langella strides into a freezing hotel room. An elegant man whose golden skin is set off by a crisp navy shirt. He walks, talks and breathes with a certainty in himself, a comfort in his own skin, a contrast to the man I’d seen on screen the previous evening as the sweaty-faced President Nixon.

It was a performance that was mesmerising in its complexity; he mastered being at the same time a bully and a victim, bitter and accepting, humbled but not diminished. The Hollywood buzz is that the 71-year-old Langella’s long-overdue Oscar nomination is about to arrive after 45 films and 70 plays. (He has recently been nominated for a Golden Globe for best actor for his role as Nixon.)

He’s renowned for his sensuous Dracula on Broadway in the 1990s. He has always based himself in New York; the theatre is his lifeblood. If he were British he would have been knighted by now. As it is, he has had to settle for the label of “America’s greatest actor”. Actor is what he is and what he’s always been. He describes it as a calling, as if to a priesthood. He is not a celebrity. He doesn’t do talk shows. He doesn’t need or want to be known, and this is the only interview he has conceded to do.

He asks me do I like writing for The Sunday Times Magazine, does it make me feel good? He’s concerned that I should feel good. So much so that when he sees me shivering in the over-air-conditioned room he turns it off and rushes into the bathroom and wraps me in white fluffy towels. “Your goose bumps were distracting me.” He knows charm. He knows poise. One wonders what exactly he found in common with Nixon.

“It was not my intention to make him likable, it was my intention to make him human and show all the monsters rolling around in his head, which probably had a great deal to do with what he did. The events are irrefutable. He probably would have been impeached if he hadn’t resigned, which was a smart thing for him to do. But it wasn’t of any interest to me to go into this part thinking ‘Let’s do a crooked drunk’ — that’s how everyone does him. And while you can’t forgive the actions, you can come to understand the human being who made those actions. Why should we judge each other so harshly?”

Indeed, Peter Morgan’s play Frost/Nixon, which preceded the film in both the West End and Broadway with the same two protagonists — Langella as Nixon and Michael Sheen as David Frost — in itself started a rethink over the Nixon years. The movie is about how the gauche Frost achieved what American journalists, broadcasters, politicians or lawyers had been unable to do: get Nixon to crack and admit culpability. The film raises many other questions — are there not parallels between Nixon’s decision to escalate action in Vietnam and Cambodia, and Bush’s decision to invade Iraq? Have there not been other dirty-tricks campaigns in presidential elections? The story hinges on the fact that Nixon colluded in the break-in at the Watergate office complex where the democratic party was planning its strategy for the next general election. He tried to cover up his involvement but was caught out because he had all his conversations at the White House taped. Langella give Nixon’s confession a strange kind of pathos. “I think that Ron Howard’s movie humanises him even more than the play.”

Sometimes dialogue or theatricality is lost when stage becomes screen, but in this case something was added. “There was a physical difference as well. I had to lay down in the make-up chair for two hours every morning. Even though the make-up is incredibly subtle and not detectable, it took two hours to create it.

“Physiognomy is destiny. Had he had a different face, a more charming smile, he wouldn’t have come out so bad. He was just somebody they liked to kick around and make fun of because it was easy.”

One of Nixon’s granddaughters saw the play and said to Langella: “Thank you for making my grandfather human.” “My belief is, if you don’t get the soul of a character, you haven’t got him,” Langella says, “and that’s my aim, to find his soul, to find the very deepest qualities in him so I can make them alive in me. If I smack on an accent, I never get the person. So it’s a choice.

“I worked with Laurence Olivier [famous for saying that one should work from the outside in]. We made a movie together in 1978 called Dracula. He played Van Helsing and we shared suites of rooms. He kept his door open and he would pad in from his suite and have tea with me. But before he’d come in I would hear him with his dialect coach going over and over the same line: ‘I did not hear you coming down.’ [Spoken in a rich Olivier-style voice.] And then we would get on set and he would say the exact line he had slaved over all morning. He believed that if you get a walk, a gait, or a hat, then that’s the key. My belief is if you haven’t got the soul, you haven’t got him.”

One wonders about the various souls of the various beings Langella has portrayed. A lot of them dark. A lot of them troubled. He played Bob Alexander in Dave, a scheming White House chief of staff; Leonard Schiller in 2007’s critically acclaimed Starting Out in the Evening. On Broadway in Amadeus he played the bitter Salieri. He is, though, currently playing the saintly Sir Thomas More in Robert Bolt’s A Man for All Seasons. How taxing is it to keep having other people’s souls inside you?

“It isn’t very, because that’s what I do. At the moment I’m living very much in Sir Thomas More’s soul.” A little smile comes to his lips as he reminds me of the fact he is playing a saint on stage and a sinner on celluloid in the same year. “I would say of everybody I’ve ever played, Nixon has lingered with me longer and has given me more pause for introspection about my inner self, my own demons, my own masks.”

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