Sexual abuse, murder, alcoholism, domestic violence, racism, suicide and the loss of faith. It’s hardly a list of crowd-pleasers, yet John Michael McDonagh’s Calvary addresses all these issues while avoiding melodrama. Indeed, McDonagh’s script is at times deeply, darkly funny – though it may not be the humour that stays with you. Having seen the film over a month ago, this critic still feels the difficult themes gnawing at her insides.

So obviously there was no better project in which to cast a comedian, in the shape of former Black Books star Dylan Moran. McDonagh’s feature contains elements of surreal humour. Still, it’s hardly a conventional laugh-fest. Thus, Moran is required to stretch himself dramatically.

Starring Brendan Gleeson as a priest whose life is threatened by a victim of clerical abuse, Calvary has received acclaim for its beautiful performances and thematic complexity. Nonetheless, the pitch was not an easy sell. Moran’s co-star Chris O’Dowd initially turned down a part in the film. He expressed concern that it would be a hatchet job against priests, explaining he had nothing but positive memories of the clergy.

Moran, however, had no such hesitations.

“In terms of a hatchet job, it all depends on how well written the hatchet is! This isn’t a hatchet job, by any means. It’s a depiction of a place and a bunch of people reacting to these... it sounds too abstract to call them ‘issues’. They’re not. They’re realities that have played out in Ireland over the past few years and the decades before. So the subject matter didn’t put me off at all. This stuff has to be talked about.”

Writing for the UK’s Observer a decade ago, Moran declared he was “fairly anti-clerical.” It’s a credo his character seems to share for much of Calvary.

“In the film, everyone has issues with the Church, and everyone has issues with the figure of a priest – even though everyone in the community recognises that he’s a man of integrity and substance. Everybody has their own reaction to the Church, the belief systems that propped the country up for so long. It was the Church in the first instance, and then people turned to money. It’s been a shorter affair; in Ireland we’ve played with money for a much shorter period of time than with religion. Which is natural. Because you run out of money – but you never run out of despair or hope. Those taps are always flowing.”

Moran grew up in a secular household.

“I wasn’t raised with that religious tradition. It wasn’t in my house – which was unusual for the time. I didn’t know anyone else not going to Church. It was kind of a party line that was enforced in Ireland. This idea that ‘you have to be in this, why wouldn’t you be, what’s wrong with you?’ And of course everyone ran into religion in education because the Church controlled education. You had to have feelings about these people. You couldn’t just avoid them, because you ran into them all the time. For me, priests were never a source of guidance, or a receptacle of faith. They were offering answers when I hadn’t started asking my questions yet. That always seemed suspicious.”

Moran uses his stand-up to address humans fears of confronting ourselves, and the myriad of ways we try to tranquilise or intellectualise away our feelings: through religion, alcohol, self-medication or the endless prescribing of seemingly infinite “syndromes.”

“Everything is so prescriptive now,” he muses. “You’re never just depressed; it’s the absence of serotonin or whatever. There has to be a cure, for everything. It has to come packaged up. And if we’re happy, we need to ascribe it to eating more seedless fruit or whatever, because then we can brag that we did this specific thing that other people are too lazy to do and that’s why we win. Everything’s a race to a solution.”

It was in the grey areas – the uncomfortable, the unresolved, the unanswerable – that Moran found a kinship with Calvary’s writer and director John Michael McDonagh.

“What I love about his writing is that it doesn’t lead you by the nose. It wasn’t prescriptive. And he’s like that as a director. He just gives you the material and says ‘Go’, and trusts you to bring your own knowledge and awareness. And he’s like that with an audience, trusts them to come to their own conclusions, which is why it works as well as it does. It’s not sign-posted ‘Oh here’s the comic bit, and now you can feel sad.’ It’s all braided, it’s rich at all times throughout.

“That’s what life is like. It’s not easy and single-toned. My interest in a film plummets if it tells me how to think or that everything is going to be alright: all these tropes that people know intimately because we’ve all seen thousands of films. Audiences know a lot and yet they’re hardly ever spoken to directly. They’re either spoken up to or down to – usually down to. So for a storyteller to just talk to you, and allow you to interpret it yourself, and allow you the right to not feel just good or just bad; to just feel the way you’re going to feel... it’s important.”

Though Moran, who has lived in the UK since the ’90s, admits to some wariness at how steeped in American culture we in Ireland have become, he believes the Irish will never completely lose our apprecation for the dark and complex – our distinctively cynical humour, for that matter.

“I would expect that the sugar-coated stuff goes down less easily here. I would guess we don’t feel as entitled to happy endings as Americans – or maybe we know that force-feeding ourselves fake happy endings isn’t a real comfort. You can’t have Baked Alaska for dinner and expect to feel great. That’s why I liked this film, because it’s constantly looking at how you address the unanswerable, because people try to constantly throw things at it. They throw religion at it, or materialism at it, or sex or drugs or whatever.

"That roaring vacuum, that roaring space never goes away. And maybe it shouldn’t. It’s what keeps the fire going. It keeps pulling at you, and it’s never answered. And we know they can’t be filled with cheap answers, cheap films, cheap laughs. Which is why it feels empty. You don’t even believe your own craving for diversion in the end, because you just feel stupid for participating, for allowing yourself to want that diversion. This film doesn’t offer any of that. It’s not trying to instruct or preach or console, and I like that. I like the ‘messagelessness’ of it all.”

Quoting writers from Beckett to Don DeLillo as influences, Moran’s love of language doesn’t just reveal itself in his poetically rhythmic storytelling – he’s often far more explicit than that.

The title of his 2011 show, Yeah Yeah, came from a ’50s lecture on language by Oxford philosopher J.L. Austin. Austin noted that while a double negative amounts to a positive, never does a double positive amount to a negative. From the back of the audience, Columbia professor Sidney Morgenbesser muttered the perfect dismissal: ‘’Yeah, yeah.’’

Moran also gives nods to Central European writers like Emil Cioran, revealing another passion: travelling, and immersing himself in other cultures. “I love that opportunity to explore a new place. Though I travelled at an almost experimental level last year, I was in nine countries in 11 days at one point, which isn’t healthy. You don’t have time to breathe.”

Dylan has toured extensively, and was the first Irish stand-up to perform in Russia. He describes a deep affinity with Central and Eastern Europeans, a rarer sentiment than it should be. Perhaps Moran’s right to be wary of our exposure to American culture, which all too frequently represents Eastern Europeans as sociopathic Bond villains or scarred warmongers bent on world domination.

“It’s very mistaken,” agrees Moran. “It’s such an interesting place, the more you read into it. And it has so many parallels with here, it’s freaky. Ireland is built on fables and myths and stories. It’s the same over there. The folk culture is fascinating, and the culture of ‘talk’ is very similar to here. It survives there like it does here, because people have time around the table, talking and just wanting that. Talk was the mental fire you would gather around in the evening. Increasingly, all this stuff that you and I have” – he gestures to our iPhones – “and that everybody has is surrounding our communication with static. But I do think in decades to come we still be sitting around the kitchen table talking, because it’s what we want and need. And Eastern European people are like that, so I feel that draw there.”

Happily settled in Scotland with his wife and two children, Moran hasn’t lived in Ireland in years. Perhaps due to his desire to constantly challenge himself, there’s an ambivalence about ever coming home permanently.

“I think if I lived here on a daily basis I’d relax in a way I haven’t or don’t there. Just being surrounded with...” he pauses, and allows the chatter of the bar to wash into our alcove. “Just these familiar sounds. It would be interesting to come back for a year. But there’s something very attractive about drifting, about letting yourself get wrapped in your own mists.”

“Getting wrapped in your own mists” seems like the perfect metaphor for Moran’s writing process, which he describes as both a torturous and rewarding experience.

He’s working on a book, and from his mercilessly self-deprecating description - “it’s a very small piece of work, it’s tiny, miniscule, so small and pointless; just diverting rubbish” – it appears that he isn’t immune to bouts of self-doubt. He says that deadlines are a necessary evil, forcing him to hand in work that he’d otherwise pick over infinitely.

“You have to hand something in, and it’s always going to be less than what you want. And sometimes you don’t want to do anything, because as long as it’s only an idea in your head, it’s amazing. It will undoubtedly be the greatest thing that man has ever written – which is exactly why you don’t write it, because the second it becomes real is the second that fantasy evaporates. But you have to write, and presumably the more you work on it the better it will get. It can be oppressive, Which is why I do like having moments to breathe, to drift. It’s good, it’s productive, as long as you drift with a pen in your head. Otherwise you’re just floating about.”

Apart from his work, he says his family are his grounding force. With his two children now aged 16 and 12, he says he is unable to condense into words how much fatherhood has changed him. “It’s impossible to answer that question. I mean, you don’t have kids,” he says. “People become different, because it changes you.”

Laughing that he “mines them endlessly for material”, the comedian also finds himself observing the huge chasm between the challenges that faced his generation and those facing his children. He rejects the popularised notion of the over privileged millennial, and asserts that the Generation Y are facing tougher trials than we give them credit for.

“It’s very tough. On the one hand, there’s a huge level of expectation, because theoretically it’s a hugely globalised world so you can go anywhere and do anything. There’s no reason why you shouldn’t think of moving and working in Seoul or Cartagena if you want to. At the same time, it’s like you’ve got to have a plan much earlier; you’ve got to have a vicious plan very early and do anything to get there. It just feels like it’s rabid out there and so fuelled by competition. You’ve got to understand technology and marketing and international politics and how people operate in crowds and all this crap we didn’t have to understand when we were kids. There’s a narrative that young people are less mature than we were at that age because we were getting married younger. I don’t think that’s fair. We settled down to live our lives. Now it feels like you need another decade just to prepare to battle for your life.”

As for Moran’s own life, it seems to be going pretty damn well; in spite of, or maybe because of, his constant philosophising about the nature of happiness and being. So, the ultimate parting question after our analysis of Ireland’s deep-rooted pain: Is Dylan Moran happy?

He seems startled by the question.

“Am I happy? Of course!”

Hmmm, no qualifier? Sounds a bit American if you ask me.

“Well, I mean… Am I… Look, I answer that question on a minute by minute basis, leave me alone!”

There. That’s better.

Calvary is in cinemas from April 11.