It's a bright Dublin morning and a small robin has circled back for the third time to take another gander at Liam Cunningham. Could it be that the extremely personable thespian can charm birds down from trees? Or perhaps the bird, in common with most of this planet, is a Game of Thrones fan.

"I've never done a big series like Game of Thrones before," says the actor, who plays Davos Seaworth in the series. "All I knew was that it was HBO, and I'd seen what they had done with The Sopranos and The Wire. But when I started reading the script it was a no-brainer. Yes, yes, yes. Gold. Every time I turned the page."

The jewel in the HBO crown is not without its admirers, and those admirers are apt to queue up for hours. “It’s weird,” says Cunningham. “Nobody who works in a bank has 10 people waiting to say ‘I love your work’ at the end of their day. Some day it’ll pass and I’ll shave off the beard and slide back into obscurity.”

That doesn't sound all that likely. Over the past decade, Cunningham has been directed by Steven Spielberg (War Horse), Ken Loach (The Wind that Shakes the Barley) and Steve McQueen (Hunger), and has appeared with everyone from Michael Caine (Harry Brown) to Denzel Washington (Safe House).

“A lot of people think I don’t live here,” laughs Cunningham. “But I’ve never stirred. I don’t mind being away. I did a year and a half at the Royal Shakespeare Company years back. I like this place. People don’t give a shite who you are. They aren’t that impressed, or they’re too polite to annoy you. You might hear some remarks if people have a few on them. But you can find that anywhere.”

Dubliners don’t come more Dubliner than the Rotunda-born, North Wall-raised Cunningham. His father, another Dubliner, worked on the docks and was pleased when the teenage Liam found a trade and “a job for life” with the ESB.

To Zimbabwe and back

He might have had a comfortable life “driving around in my little yellow van” but instead he and his wife, Colette, made their way to Zimbabwe. The couple spent 3½ years in Africa, where Cunningham helped maintain the power supply to Hurungwe Safari Park. After returning to Dublin, boredom set in and he decided to take some acting classes.

“It was supposed to be a hobby,” he says. “But something happened. And I fell in love with it. So I decided to jack in the job.”

How did his family and friends respond? “Well, I’ll never forget my father’s reaction. I had to tell him I was going to do this. He was reading a newspaper and he didn’t even look up. All I heard was, ‘For fuck’s sake’. That was the aul’ fella’s way of boosting my ego.”

As it happens, Liam Cunningham has not been short of offers since making his professional debut in Dermot Bolger's The Lament for Arthur Cleary, which went on tour in the US after its Dublin run.

In the past few weeks he has completed work on his first video game with Mark Hamill (“Luke Skywalker!” cries Cunningham excitedly). He’ll soon be taking his youngest son, Sean, to Miami, where HBO promotional duties await, and from there he’ll travel to Comic-Con’s Hall H, with his daughter Ellen and her boyfriend: “They love all that geek and cosplay stuff.”

Donal McCann fan

Despite the 5,000-strong throng that will turn up at Hall H, Cunningham still thinks of himself as a character actor. “I’ve always admired people like Donal McCann,” he says. “He wasn’t a household name but if he put his name to something you were guaranteed a good yarn at the very least. He didn’t want to insult or patronise anyone. He wasn’t taking the money and running.”

But not taking the money and running can be tricky when you have a mortgage and three kids at home. “Yeah. Those are the real tough decisions. Saying no when there’s no money in the bank. But if you take something knowing it’s dodgy, you’re not just making a bad decision. You also have to lie about it to journalists after. And through them, you’re lying to the public. It’s awful watching someone answer the question ‘What first attracted you to the role?’ when you know it was the cheque.”

Unsurprisingly, he has rules for reading scripts. “You have to look for story. That’s obvious. If that’s not on the page you can forget it. But I also read whatever character I’m being offered. And if you can cut them out without it affecting the story, then I say no straight away.”

That same rule applies even when a film has people attached who he would really like to work with. “I used to have a big crush on Emmanuelle Béart. Who didn’t? I used to joke with the wife, ‘If I get a movie with her, its game over, love’. So I did get offered a movie with her. But the script was dreadful. So I’m still married.”

Cunningham says he has a "sticking point" about female characters who are "nothing more than damsels-in-distress". That's one of many reasons he signed up for Let Us Prey, a daring horror from first-time director Brian O'Malley. In the film Pollyanna Macintosh's good cop forms a bond with Cunningham's supernatural stranger, as a kind of apocalypse falls on a rural Scottish police station.

“I’m the devil, or the grim reaper, or whatever you want to call him. But for the harbinger of death he’s a pretty nice guy. And I love that against that you have Pollyanna playing this really strong, fully formed character. That’s what makes it.”

Let Us Prey has been a long time coming: O'Malley and Cunningham first worked together on the short film Screwback more than a decade ago. Maybe it was the long wait, and a lot of pent-up creativity, but the project is easily the most baroque film of the year thus far.

"I don't want to call it a date movie," says the 54-year-old. "But it's a cool thing to see with your partner: a few frights, a few laughs, a bit of Gone with the Wind. You have to go with it. Watch it with a smile and your tongue in your cheek."

• Let Us Prey is on release

THE DEVIL’S IN THE DETAIL: SATAN ON SCREEN

Damn Yankees (1958): Salvation Army founder William Booth famously asked: why should the Devil have all the best tunes? But this 1955 musical distributes its showstoppers evenly, as a middle-aged baseball fan attempts to wriggle out of a Faustian pact. South Pacific's Ray Walston brings the eternal trickery.

The Devil and Daniel Webster (1944): Walter Huston's Mr Scratch (above) does battle with a US senator for the soul of an American farmer. Who will persuade a jury comprised of some of the most evil men in American history?

Angel Heart (1987): It's a question that will echo through the ages. When Mickey Rourke agrees to work for Robert De Niro's Mr Louis Cipher, how on earth does he not spot the wordplay?

The Passion of the Christ (2004): When the devil (Rosalinda Celentano) starts hissing at you in Aramaic, you do tend to pay attention.

The Devil's Advocate (1997): The Dark Lord does not come more twinkly and loud. Al Pacino provides the noise, the big hand gestures and the evil.