The film business has its own eccentricities. Domhnall Gleeson and I are at the Soho Hotel in central London to discuss (among many other things) his performance in Alejandro González Iñárritu's liver-chewing, face-bashing, blood-vomiting frontier epic The Revenant.

Why would we not be here? The film has already been celebrated as an unforgiving masterpiece and last Sunday picked up Golden Globes for best picture, best director and best actor (Leonardo DiCaprio).

Gleeson – who plays a decent man in impossible circumstances – is fast becoming the most sought-after actor of his generation. Domhnall's long face and melodic voice have been unavoidable over the past year. Look, there he is communing with cyborgs in Ex Machina. He was the reassuring face of home in John Crowley's Brooklyn. He was the totalitarian General Hux in Star Wars: The Force Awakens. Of course, we'd like to speak with him.

Here's the odd thing. Both of us have flown over from Dublin to be here. Domhnall does have other things to do. As we speak, his dad, Brendan Gleeson, is preparing for the premiere of Suffragette. The younger Gleeson also managed to get to see his old pal Martin McDonagh's new play Hangmen.

“It was amazing,” he raves. “Going to one of Martin’s plays is more like going to a football match or a concert. There’s that level of excitement. You come out at the interval and there’s not enough time to say all the things you want to say.”

Of course, Gleeson's big break came in a McDonagh play. After all that's happened, it's easy to forget that he first emerged above ground in the Broadway production of The Lieutenant of Inishmore back in 2006.

"Oh, I am pretty certain I wouldn't have been an actor if I hadn't read for The Lieutenant of Inishmore. If I hadn't gotten it, the path would have been very different."

Anyway, where were we? Oh yes. Such are the oddities of the trade that we have both travelled across the Irish Sea (in different aeroplanes) to have this chat.

Gleeson is now at the stage where agents will begin to wonder whether he might like to take an apartment in Santa Monica or West Hollywood. I imagine a trail of hundred-dollar bills being laid out to lure him westwards.

“It hasn’t struck me to move at all,” he says. “No. That’s not even a lie I’ve prepared for journalists. Ha ha! That’s really true. There has never been really any pressure on me at all yet.”

Mind you, he can’t have seen much of his own couch over the last year and a half. When you mention to actors that they seem suddenly ubiquitous they will often hum and haw about deceptive release dates. This film was made two years ago and has only emerged now. That film ended up being rushed into cinemas. Those sorts of things.

But there's no way of finessing the mathematics here. In 2014, Gleeson appeared in Lenny Abrahamson's Frank, John Michael McDonagh's Calvary and Angelina Jolie's Unbroken. Now all this. Gleeson has surely been working his arse off.

"Yes, I have," he says. "I did about a year of working straight through. There were four or five straight jobs. But I wanted to try that. I had worked with Michael Fassbender on Frank and I'd seen the way that he turned energy into more energy, rather than: work, crash, rest; work, crash, rest. He goes from one to the next and, while he's on one job, that's all he thinks about. I wanted to see how I would deal with not taking two months off to prepare. At first I had to do that because I'd nothing else to do."

There's also not much he could have turned down on that list. Right? He's not going to turn down Star Wars. He's not going to turn down The Revenant.

“Yes. You’re right there. No question.”

Like his dad, Gleeson is articulate and keen to structure answers in formal sentences. He can be cautious, but he will usually explain the reasons for his caution.

We've seen him essay any number of eccentrics over the last decade – including Bob Geldof in When Harvey Met Bob and Bill Weasley in the last Harry Potter film – but his speciality is a sort of wounded, vulnerable decency. It was, thus, all the more interesting to see him play a fascistic maniac in Star Wars: The Force Awakens.

He is set to appear in the next formal episode of the sequence, but, such are the absurd fears for “spoilers”, it’s hardly worth asking him what he knows. The director of MI6 must feel less burdened with dangerous secrets.

"I was talking to my friend who's a teacher – he was in a music video I made with my brother Brian – and one of his students asked him about my character in Star Wars. He knew that my friend knew me. Now, that was made easy by the fact that I'd told my friend nothing. When you can still say nothing at all it's easy. It's when you can say a certain amount it becomes difficult. Coming up to the film, I can say he's a bad guy. I can say his name. He speaks with an English accent. He works on Starkiller Base. I have to remember to say those four things and no more."

Does some memo come round clarifying that? How does he know what he can say?

“Frankly, it’s common sense,” he says. “I just don’t want to be in charge of this sort of information.”

The long road to Star Wars began, bizarrely, with a speech at the Irish Film and Television Awards. When he was 16, Gleeson accepted an award for his father who was shooting overseas. The evening could have been a disaster. Brendan had passed on three sheets of text and, at the last minute, Domhnall realised he would have just 30 seconds at the podium. His improvised confusion charmed the audience.

“I wasn’t really a showoff. I was quite shy,” he says. “I made some stupid joke about how teachers know I’m really good at skimming. It got a lot of laughs. It was live on TV and it had been quite a sombre ceremony. I lightened the mood. I decided to make a few jokes and I got an agent out of that.”

How delightfully strange. Had he any thoughts of becoming an actor at that stage?

“No. I had been in the transition-year play. I really enjoyed that. My ambitions were about writing and directing at that stage. I didn’t actually do anything with the agent for two years.”

I wonder what his father made of it all. Actors are often more wary than civilians when their children threaten to take to the stage. They know the challenges. They’ve met the kids who haven’t made it.

“In a way you’d have to ask him,” he says. “My take on it is that all good parents will want their children to be happy. Acting is a difficult career in terms of the odds that you will end up making it. So many are out of work. I would understand a parent being wary. But if you want your children to be happy and this is what makes them happy now, then what choice do you have? So they were supportive.”

And his mother had at least as much to say about it as his dad?

“Precisely that. That’s an important point. She had as much to say and offered as much support.”

Gleeson now finds himself carried along by an astonishingly vigorous wave of Irish film. It requires no hyperbole to assert that domestic cinema has never been healthier. Lenny Abrahamson's Room has gathered a swathe of rave reviews and is a big player in the continuing awards season. John Crowley's Brooklyn, featuring Gleeson in a key role, has been doing equally well. An unprecedented seven Irish films are set to play at the upcoming Sundance Film Festival. He must have some insight into what is going on.

“You’ll have to trust me when I say I am not dodging the question, but I don’t really think of things as ‘Irish’ or ‘not-Irish’ when it comes to work,” he says cautiously. “Michael Fassbender is of the world and for the world. My work is not improved by being judged next to his just because we’re both Irish. Not in my mind, anyway.

“If Lenny does well I will be proud to know him. But I know people who are English who I would be similarly proud of. It’s for the people in the Film Board to consider what’s Irish and to promote that. That’s an important job, but it’s not my job.”

Now we have The Revenant. Yikes! Few films have worked so hard to put the viewer through the wringer. Leonardo DiCaprio plays a 19th-century frontiersman who, after being gored by a bear and abandoned by his colleagues, sets out on a gruelling odyssey of revenge.

Innards are pulled outwards. Brains are blasted. Blood is chilled. If reports are to be believed, the cast suffered almost as much as the pioneers on whom the story was based. Is this true? Or were they emerging from luxurious caravans for 20 minutes of sporadic pretending?

"No. That was Alejandro's nightmare," he laughs. "He didn't want a bunch of actors turning up with coffee in hand and still laughing after having watched Always Sunny in Philadelphia. 'Huh, what am I doing?' Then having to add in CG breath afterwards. He set it up to be really, really hard going. It was very taxing. He wanted to push everybody, including himself. He certainly achieved that. When I saw the film I saw all that. I felt it had been worth it."

Worth what? Give us some sense of what he and his colleagues had been through.

“It depended on the day. But you’d be at high altitude carrying a lot of stuff. Certain days you’d be in and out of a river and it would be minus 20. That’s just insane. Getting dry and keeping warm is an issue. Then there’s so little light. When it gets round to being able to shoot that’s weighing on your shoulders. You really want to get it right. That is alleviated when Alejandro says [happy up-note] ‘Cut!’ instead of [sombre down-note] ‘Cut!’”

The film is based on Michael Punke's novel concerning the true story of Hugh Glass. Gleeson, back in honest-Joe mode, plays Andrew Henry, a fur trader who was known for his integrity and honesty. One gets the sense of a man working hard to shield his conscience from the everyday pressures of human congress and the unmanageable forces of nature. One must assume that, isolated in bleak corners of Canada and Argentina, the cast was forced into unusual intimacy.

Will Poulter, Tom Hardy and Lukas Haas are among those offering support to DiCaprio and Gleeson.

“There is that with cast and crew,” he says. “It’s also a male-heavy cast and that’s strange. Most of us were living in the same hotel. So our only company was each other. That’s also strange. The characters are all at loggerheads in the film. So you’re in this community, but weirdly you also feel your job is to protect your character at all costs – even if he’s behaving badly. It’s us against the elements and it’s us against one another.”

Now 32, Gleeson could hardly be more perfectly placed. He has just left an extraordinary year's work in his wake. Aside from those film roles, he also managed to appear with his dad and brother Brian in Enda Walsh's The Walworth Farce at the Olympia. He has the distinctive face for character roles, but, in oddball gems such as Ex Machina and Frank, has also shown an ability to become the audience's eyes.

After all that hubbub, Gleeson is finally getting a chance to take a breath. Star Wars Episode VIII begins soon. He has recently finished shooting Doug Liman's Mena, an adventure flick starring Tom Cruise. What can he tell us about that stellar Cruisian enigma?

“He’s great,” Gleeson says. “Again, it’s about pushing yourself and saying: that’s the most I could have got out of that scene. As long as you are serious about it then I want in. He still has a hunger for that and that’s inspiring.”

Following which irresistible message, we shake hands, wish each other well and prepare to make our way back home to the same city. The Revenant is on general release