For anyone who looks toward their later years with trepidation, Sir Anthony Hopkins (“Tony, please”) is a proper tonic. He is 79, and happier than he has ever been. This is due to a mixture of things: his relationship with his wife of 15 years, Stella, who has encouraged him to keep fit, and to branch out into painting and classical composition; the calming of his inner fire, of which more later; and his work.

Hopkins loves to work. Much of his self-esteem and vigour comes from acting – “Oh, yes, work has kept me going. Work has given me my energy” – and he is in no way contemplating slowing down. You can feel a quicksilver energy about him, a restlessness. Every so often, I think he’s going to stop the interview and take flight, but actually he’s enjoying himself and keeps saying, “Ask me more! This is great!”

We meet in Rome, where he is making a Netflix film about the relationship between the last pope (Benedict) and the current one (Francis). Hopkins is playing Benedict, Jonathan Pryce is Francis. He is enjoying this – “We’re filming in the Sistine Chapel tomorrow!” – and we are both relishing the lovely view across the city from the penthouse suite in the hotel where he’s staying. Still, he declares that the film we are here to talk about, the BBC’s King Lear, filmed in England and directed by Richard Eyre, is the piece of work that has made him truly happy. “I felt, ‘Yes, I can do this.’ I can do this sort of work. I didn’t walk away. And it’s so invigorating, because I know I can do it, and I’ve got my sense of humour, my humility, and nothing’s been destroyed.”

He’s played the part before, at the National Theatre in 1986, with David Hare directing. “I was… ” – he counts in his head “… 48,” he says. “Ridiculous. I didn’t realise I was too young. I had no concept of how to do it. I was floundering.”

I come from a generation where men are not very good at receiving or giving love. We don’t understand it

Now, he feels he’s got Lear right, and few would disagree. In a star-studded cast – Emma Thompson plays Goneril; Emily Watson, Regan; Jim Broadbent, Gloucester; Jim Carter, Kent; Andrew Scott, Edgar – it’s Hopkins who dominates. He is fantastic: his white hair close-cropped, his manner like a heavy-headed bull, a scary tyrant losing his powers, a drinker who flips into terrifying rage.

Hopkins’ theory is that Lear’s wife died giving birth to Cordelia, and Lear brought her up, his favourite, as a tomboy. Of the older two daughters, Emily Watson said, “and I agree with her, that they have become monsters, because he made them so”. Hopkins believes that Lear is terrified of women, can’t understand them. Hence the awful specificity of the curses he rains on his older daughters, damning their wombs. He seeks refuge in men, surrounding himself with a boisterous male army. The scenes where Lear wants to bring his retinue to Regan’s house are reminiscent of an awful, all-boys-together drink-fest.

“I come from a generation where men were men,” Hopkins says. “There’s nothing soft or touchy-feely about any of us, where we were from in Wales. There’s a negative side to that, because we’re not very good at receiving love or giving it. We don’t understand it. After Richard Burton died, his brother Graham invited me to the Dorchester where they were all having a get-together, the wives and the men, all the sisters and brothers. All pissed. And I noticed the women were sipping their ports and brandy, but all the men were, ‘Come on, drink! Drink!’ I thought, ‘There’s something very Greek about this.’ Men together. You know, like the bouzouki dancers. It’s not homosexuality, but it is a sexuality, a kind of bonding. That’s what I was thinking of.”

Hopkins often uses his past to find his way into a character. Small incidents that stick in his mind, real people who inform. In the scene with Kent, Edgar and the Fool, as Lear descends into madness, he has all three line up on a bench and addresses them with the wrong names. Hopkins decided that Lear had seen his father drown three puppies when he was young and believed his friends to be those dogs. “Cruelty to an animal stays with you for the rest of your life,” he says. “I once witnessed something like that, but I can’t think of it too much, it’s too upsetting. But that little kernel of an event doesn’t go. It grows with you.” When he portrays deliberately scary people – such as Hannibal Lecter or Robert Ford in the Westworld series – he plays them quietly, emphasising their sinister control. His Lear, though, is explosive. “He’s completely bonkers – he laughs at the storm. That’s what I like about him.”

In the film, Hopkins uses a horseshoe as his crown. He asked a friend, Drew Dalton, a props guy on Westworld who is also an Idaho farmer, to get it for him, and he told him it was from an old horse, born in 1925. When Hopkins talks about this horse, he gets a little teary. “I carry the horseshoe with me wherever I go now. I still get emotional about it – the power, and the loneliness, and the pain of that horse. That’s Lear.”

Facebook Twitter Pinterest As Lear in 1986. ‘I didn’t realise I was too young. I had no concept of how to do it. I was floundering.’ Photograph: Donald Cooper/photostage.co.uk

Tears come easily to him, especially when he talks about hard work, old age, masculinity. His father, Dick, was a baker, a tough, practical man, born of another baker. But, Hopkins says, as he got older, small things would upset him, “like if he made a mistake in his car and drove off a ramp instead of getting it just right, he’d break down crying. Towards the end of his life, he used to drink, and he was unpredictable. Never violent, but sudden turns of rage, and then deep depressions. Turned on my mother, turned on me. I was old enough, so it didn’t bother me. We didn’t speak much before he died. He resented me for something. I understood it, I could get it, and I thought, ‘What a terrible, lonely horror, for people at the end of their lives.’”

It’s easy to see how he drew on this for Lear. Hopkins has a daughter, too, Abigail, from his first marriage, but they don’t have a relationship, so there was no inspiration there. “No. I accepted it years ago. It’s her choice and she must live her life. I say to young people, ‘If your parents are giving you trouble, move out.’ You’ve got to let go. You don’t have to kill your parents, but just leave if it’s holding you back.”

Facebook Twitter Pinterest In Lear in 2018, with Florence Pugh as Cordelia. Photograph: Ed Miller/BBC/Playground Entertainment

Lear came out of another BBC film, an adaptation of Ronald Harwood’s The Dresser, also directed by Eyre and broadcast in 2015. Hopkins was the ageing, belligerent actor Sir, who is preparing to play Lear; Ian McKellen was Norman, his dresser. Hopkins had wanted to do the play since picking up a copy in a bookshop in Los Angeles, where he lives: “It opened the valves of nostalgia.”

When he first became involved in the theatre, in the late 1950s, Hopkins was a stage manager, touring northern towns, meeting “old, wrecked, alcoholic, wonderful” vaudeville comedians who’d worked during the war, talking to stage hands who knew the technique of dropping the curtain for comedy (fast) and tragedy (very slow). Then he joined the National in the time of Olivier and Gielgud. He was impatient for success. “Oh,” he says, “I had nonspeaking parts, messengers and God knows what, and I was very disgruntled, because I wanted to be bigger. So I went to the casting director and said, ‘Who do you have to sleep with to get a part around here?’ I’d only been there three weeks!”

Facebook Twitter Pinterest In The Dresser with Ian McKellen. Photograph: Alamy Stock Photo

The casting director was taken aback, but mentioned him to Olivier, who gave him a part as an IRA man in Juno And The Paycock. Hopkins knows now that his hubris was ludicrous, but he was anxious to get to the action, and still is. “I think, with life, just get on with it, you know?” he says. “We’re all going to die, and that’s a great motivator.”

He tried to quieten down, but his mother said, ‘Why don’t you just be the bastard that you really are?’

At the National, he met the actors Ernest Milton, Donald Wolfit and Paul Scofield, and he drew on these memories to play Sir (Harwood had been Wolfit’s dresser). He surprised himself by how much he enjoyed making The Dresser. It was a sort of revelation. “When I was at the National all those years ago, I knew I had something in me,” he says, “but I didn’t have the discipline. I had a Welsh temperament and didn’t have that ‘fitting in’ mechanism. Derek Jacobi, who is wonderful, had it, but I didn’t. I would fight, I would rebel. I thought, ‘Well, I don’t belong here.’ And for almost 50 years afterwards, I felt that edge of, ‘I don’t belong anywhere, I’m a loner.’ I don’t have any friends who are actors at all. But in The Dresser, when Ian [McKellen] responded, it was wonderful. We got on so well and I suddenly felt at home, as though that lack of belonging was all in my imagination, all in my vanity.”

He’s always called himself a loner – “alone, loner, solitary”, he says to me – and in past interviews his outsiderdom has become almost his headline characteristic. But he and McKellen bonded, regaling each other with old stories instead of rehearsing. Having felt, for all those years, unwanted by the establishment, the establishment was making him welcome. He also realised that he wanted to do Lear for real.

Facebook Twitter Pinterest His last stage play, M Butterfly, in 1989, with Glen Goei. Photograph: Nobby Clark/ArenaPAL

Not on stage, though. Despite his nostalgia, Hopkins hates the theatre. In 1973, he walked out of Macbeth mid-run at the National and moved to LA. The last stage play he was in was M Butterfly, in the West End in 1989. It was a torment, he says, the tipping point being a matinee where nobody laughed, “not a titter”. When the lights came up, the cast realised the entire audience was Japanese. “Oh God,” he recalls. “You’d go to your dressing room and someone would pop their head round the door and say, ‘Coffee? Tea?’ And I’d think, ‘An open razor, please.’”

He can’t stand being unproductive, working without a point; it drives him mad. David Hare once told Hopkins he’d never met anyone as angry: “And this was when I was off the booze!” He gave up drinking in 1975. For a while, he tried to quieten down his personality (“I was ever so careful”), but his mother told him it wasn’t working. “She said, ‘Why don’t you just be the bastard that you really are?’ She said, ‘I know what you’re like, you’re a monster.’ I said, ‘Yes.’ She said, ‘Well, OK then, be a monster.’

I don’t have a temper any more. I get impatient, but I try not to judge

“But the anger, you begin to channel it,” he says. “I’m very happy I’m an alcoholic – it’s a great gift, because wherever I go, the abyss follows me. It’s a volcanic anger you have, and it’s fuel. Rocket fuel. But of course it can rip you to pieces and kill you. So, gradually, over the years, I have learned not to be a people-pleaser. I don’t have a temper any more. I get impatient, but I try not to judge. I try to live and let live. I don’t get into arguments, I don’t offer opinions, and I think if you do that, then the anger finally begins to transform into drive.”

Now, if he’s not acting, he paints, or plays the piano. He released an album of classical compositions, Composer, performed by the City of Birmingham Symphony Orchestra in 2011, which was well-received. “Hopkins writes with considerable flair and confidence,” said one critic, while Amazon gives it four stars. He began painting at the behest of Stella, who saw how he decorates his scripts. He goes over his lines around 250 times, until he can recite them backwards, sideways, in his sleep. Every time he reads them, he draws a doodle on his script, and the doodles, which start as small crosses, grow enormously large, covering all the blank space. Stella saw this and got him to paint “favours”, little presents for their wedding guests.

Facebook Twitter Pinterest Hopkins with his wife, Stella. Photograph: Alamy Stock Photo

“She said, ‘Well, if they don’t work, no one’s going to put you in jail,’” he says. And nobody did, because his paintings are pretty fine; they sell for thousands of dollars. He shows me some on his phone. They’re expressionist, full of bright colours – “South American colours: Stella is Colombian” – and he’s working towards a show next year in St Petersburg, which he’s very excited about.

“Ask me more questions!” he says. He doesn’t want to waste time sitting around while the photographer sets up. We talk animals. He and Stella collect stray cats and dogs. We talk politics. He doesn’t care about Trump; he doesn’t vote. He takes a widescreen approach to politics, because focusing on the detail makes him too unhappy. “I don’t vote because I don’t trust anyone. We’ve never got it right, human beings. We are all a mess, and we’re very early in our evolution. Look back throughout history: you have the 20th century, the murder of 100 million people, barely 80 years ago. The 1914-18 war, the civil war in America, slaughter, bloodshed… I don’t know if there’s a design in it, but it is extraordinary to look at it and get a perspective. I think, ‘Well, if it’s the end, there’s nothing we can do about it, and it’ll blow over, whatever happens.’”

He remembers talking to his father on the phone during the Cuban missile crisis (“and I was a raving Marxist then”) and his father remarking that the bomb would be dropped on London, so Hopkins would be all right, “because the bomb will drop on you, so you won’t know much about it. But in Wales, we’ll suffer the fallout.” His dad also once said to him, about Hitler and the second world war, “Six years later, he was dead in a bunker. So much for the Third Reich”, which makes me laugh.

I did know about the person [Weinstein], about his sexual stuff. I know he is a rude man and a tyrant. But I avoided him

Now he avoids news and politics, for his peace of mind. “In America, they’re obsessed with healthy food,” he says. “They tell you, if you eat junk food, you get fat and you die. Well, television is run by money and corporate power and sponsorship. It’s junk food for the brain. Toxic.” If he’s not busy, he orders books online and sends them to friends – Wake Up And Live! by Dorothea Brande, The Life-Changing Magic Of Not Giving A F**k by Sarah Knight – or watches old films and TV on his iPad. He was obsessed with Breaking Bad, and wrote a lovely letter to Bryan Cranston extolling his acting; now, he likes watching Midsomer Murders, The Persuaders and Rosemary & Thyme.

We talk a bit about the #MeToo movement. Hopkins says, about Harvey Weinstein, “I did know about the person you are referring to, about his sexual stuff. I know he is a rude man and a tyrant. But I avoided him, I didn’t want anything to do with people like that. Bullies.” And actually, despite his desire to live and let live, Hopkins often calls bullies out: when John Dexter, the director of M Butterfly, started shouting at everyone in the cast, Hopkins told him to stop. “I said, ‘John, you don’t need to do this. You’re a great director. Stop it.’ And he cried. I mean, I understand if people are bullies. They’ve got their problems. I can’t judge them, I won’t make fun of them at awards. It’s correct for women to stand up for themselves, because it’s unacceptable. But I don’t have a desire to dance on anyone’s grave.”

He understands that we can all be terrible, and we can all be kind. Fame and power have nothing to do with it. I tell Hopkins something the singer Tony Bennett once said – “Life teaches you how to live it if you live long enough” – and he is delighted. “How extraordinary. What an amazing thing to say! You know, I meet young people, and they want to act and they want to be famous, and I tell them, when you get to the top of the tree, there’s nothing up there. Most of this is nonsense, most of this is a lie. Accept life as it is. Just be grateful to be alive.”

He shows me a picture on his phone. It’s of him aged three, with his dad on a beach near Aberavon. His dad is grinning. Hopkins is a cherubic child, with golden curls, caught somewhere between laughing and crying. “I was upset because I’d dropped a cough sweet.” He keeps it because it reminds him of how far he’s come.

“I think, ‘Good God, I should be in Port Talbot.’ Either dead, or working in my father’s bakery. For some inexplicable reason I’m here, and none of it makes sense. And I look at him and I say, ‘We did OK, kid.’”

• King Lear is on BBC2 on Monday 28 May.

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