Director Jim Sheridan has been making films about Irish national concerns for over 30 years, and his latest movie The Secret Scripture is no different. Adapted from Sebastian Barry’s novel, the story addresses the divides between Protestants and Catholics, Irish nationalists and RAF pilots – and of course, the abusive relationship between the Church and its followers. Vanessa Redgrave and Rooney Mara both play Rose, a woman who is institutionalised for decades after being accused of murdering her newborn child. It was this character who drew the 68-year-old director to Barry’s novel.

“The story of the woman being fucking locked up, you know?” says Sheridan incredulously. “And of someone creating secret scripture, their own story. I kind of have this theory that men used to write a lot because they couldn’t have babies, you know? And create their own characters. And here’s this woman whose baby is taken from her and she writes this story to bring the character back to life. That seemed to me fundamentally interesting.”

When I ask Sheridan if it feels like his films are his babies, he agrees that “it does a little bit, and so you can never be negative about them. And then you’re finished with it, you never see it again – the child disappearing as an adult!”

Sheridan never deliberately watches his films back, but occasionally comes upon them while flicking through TV stations.

“I saw In The Name Of The Father recently and thought, ‘Fucking hell, was that in it?!’ It becomes a new experience rewatching it. But I never have the experience that other directors have rewatching stuff and thinking ‘I’d do that differently.’ Because I spend a lot of time beforehand trying to figure it out.”

Sheridan has been a writer on most of his films, whether credited or not, and he and his late screenplay writer Johnny Ferguson made significant changes when it came to adapting Sebastian Barry’s novel. One major change was making the priest who becomes obsessed with Rose a young, handsome man played by Divergent heartthrob Theo James.

“I didn’t want an old fart of a priest going after her, we’ve just seen that so many times,” he explains. “I felt there was more danger in a young guy who has the vulnerability of being sexually attracted to her, and that turns into hating her. That felt more interesting than an old guy who has gone past it and can’t get it up.”

Despite Sheridan’s care when it came to adapting the novel, Sebastian Barry has been critical of the film, which has been a difficult situation for the director to navigate.

“I think really if you’re a writer, you either need to let it go or do it yourself,” he asserts. “Emma O’Donoghue did her own script for Room, and whether you agree the movie’s a great movie or not, by writing it you are taking responsibility for it. By giving it away, you’re believing that it can be done. I don’t know, it’s hard, because I admire Sebastian as a writer and the book is beautiful. A movie is just a different thing. And it’s not like there was a misunderstanding, I spoke to him once. I don’t feel like the experience was soured. I get that if you go to see the film of something you’ve written and it feels very different, you might feel like, ‘Why the fuck did I bother writing the book?’ I understand it. I dunno, maybe the better course is ‘no comment’?”

While The Secret Scripture addresses how religion and the Church and Catholic beliefs seeped into every aspect of life in Ireland during the 1940s, Sheridan firmly believes that cinemagoers are as devout about their own belief systems – and their film preferences reflect that.

“Movies are based on belief,” he says. “It’s a binary system for the audience; you believe in what’s happening onscreen, or you don’t. And then there’s the belief system that’s coming offscreen that the audience has to go along with. And you can see that in the way that independent movies and European movies never play or do well in Trump’s red states. There’s a different value system, and the result is that there’s a divide between Europe and America, and now America is like two countries now, too.”

Sheridan believes that the seemingly infinite amount of stories glorifying all-powerful men has had a major impact on the cultural and political landscape of America.

“If you keep doing Iron Man and Spiderman and Superman, you’re going to get Iron Man in the White House,” he observes, wryly. “Having these men believing that they and only they can save the world; making these movies over and over again is obviously playing into this sense of loss that people want to regain.”

For Sheridan, staying attuned to local and national politics is of great importance, and a speech he made supporting the homeless activism group Home Sweet Home went viral. For the director, it’s particularly important to use his platform to help those who haven’t enjoyed his financial success.

“You do a little bit become part of the one percent,” says Sheridan about becoming famous and wealthy. “It’s not as drastic as in America because Irish films aren’t as commercially successful – but there’s definitely a separation that occurs when you’re successful. And Apollo House was good for reminding me of that, of bringing me back to my roots. Because you get used to it, you do. I’ve seen a lot of people who have got a little bit of money and their lifestyle changes and that becomes the new normal. We get used to money very quickly and forget pain – and empathy. And I think a lot of people’s connectedness to art is through their roots.”

So does it get harder for the director to bring passion to his films now, compared to his earlier work when his past and raw emotion may have been easier to access?

“It might be getting a little harder to draw from my emotion now than it was in earlier years,” he admits. “But I’m doing a movie about the IRA escaping the Long Kesh and that interests me. I’m looking at it like it’s the opposite of a Scorsese or a Tarantino – it’s about non-violence. And that’s hard to do. It’s easier to do violence, and it’s about how the smarter you get, the more you’re drawn to non-violence. Which is about my interest in that time, but also about me getting bullied at school. So it’s still there!”

The Secret Scripture is in cinemas now.