Cillian Murphy is arguably the most consistently impressive screen actor that Ireland has produced.

He’d deny it if you said so (he’s from Cork after all), but in a career that sees him alternating between low-budget independent hits and multimillion-dollar blockbusters, he has yet to put a foot wrong. 

From the beginning Murphy, 34, has been notoriously protective of his private life and hasn’t gone in for the usual trappings of celebrity -- booze and all the epic benders that burn up Internet gossip sites. He’s never challenged anyone to a duel, or got drunk at the airport, or dropped a sex tape before the startled public’s gaze. As Hollywood celebrities go, he’s unusually low-key, and that’s how he wants to keep it.

“I’m just not very good at it really, and I never have been,” Murphy, who hails from Douglas, Co. Cork, tells the Irish Voice during a recent interview.

He mentions no names, but it's no secret that some of his famous friends like Jonathan Rhys Meyers and Colin Farrell must envy his self-control.

“Some people are just naturally good at that stuff (being stars). I’m not,” he says.

“For me, the publicity should always be the work and you can just judge me on that. That’s the way I try and keep it, purely because I’d be rubbish at it otherwise.”

This week Murphy stars in "Inception," the most anticipated big-budget thriller of the summer directed by Christopher Nolan ("Batman Begins," "The Prestige," "The Dark Knight.") This time, Murphy (who has appeared in several of Nolan’s films) shares screen time with actors like Leonardo DiCaprio and Michael Caine and once again he does what he’s paid to do -- provide the most captivating portrait in the film.

Controversially not many film critics have seen "Inception" yet, in an unusual attempt by Warner Brothers to shroud the storyline in secrecy right up to the opening date. This has led to a lot of online grousing. It must really stink, assumed the critics, if they’re being that paranoid. 

But the decision to keep it under wraps until opening day has turned out to be a wise one. Going in blind you may anticipate Inception will just be a second-hand retelling of the Keanu Reeves sci-fi classic "The Matrix." It’s not a bit.

In fact, "Inception" is a dark and surprisingly thoughtful thriller that explores some mind-bending ideas while it’s making you jump out of your seat. Set inside the minds of each character, literally inside their dreams, in Inception anything is possible -- you can go anywhere and become anyone.

Sounds great, until you remember that dreams can turn into nightmares in a heartbeat. That’s what gives Inception its fascination and its strange power.

Nolan makes action flicks that are also completely absorbing philosophically, even when the material gets noticeably thin or contradictory. He knows how to fire on all cylinders in a way that ensures he has few equals in the thriller genre. It’s a way of working that Murphy clearly enjoys.

“If you say this film has the structure of a heist movie I would be what they call the mark. Traditionally that’s not a very interesting role to play. The layers wouldn’t be very complex, you know?” says Murphy

“But with Chris at the helm, he gave my character a lot of color. I tried to play him as a petulant child who’s in need of a lot of attention from his father. He has everything he could ever want materially, but he’s deeply lacking emotionally.”

To find some truth behind his role, Murphy says he delved into his own personal life with his artist wife Yvonne McGuinness, and their two children.

“I’m a father of two sons myself, and in the role, I thought about my own relationship with my dad. To add to that the idea of living in the shadow of someone so immensely powerful (in the film Murphy’s father is a tycoon and a Rupert Murdoch-like figure) must have a huge effect on a person,” says Murphy.

“I also looked at the Murdoch family and how his sons have dealt with his achievements, and it was interesting to play and to try and give him some humanity.”

Some people may be surprised to discover that when they first met, director Nolan was contemplating casting Murphy in the role of Batman in "Batman Begins."

“There was a few of us going up for that role. We met years ago and I think he’d just done Insomnia. We chatted and we got on very well. He talked to me about the Batman thing and I said, ‘Me? I don’t know man. But sure I’ll come in and audition,’” Murphy recalls.

Murphy ended up playing Batman’s nemesis Scarecrow, which was a relief to him personally, he says.

“I did the test and it was obvious to me that Christian Bale was the best choice (for Batman) and he just seemed perfect for it. But Nolan saw something in the test and then he talked to me about Scarecrow,” says Murphy.

Having starred in several of Nolan’s films now, there’s a trust that has developed between the Irish actor and the English director.

“I think that’s probably the main reason people do re-collaborate. You do have a level of shorthand. You can get rid of all the preliminaries and go straight to the work,” says Murphy.

“I’ve had the pleasure of working with Chris a couple of times and there’s a level of trust there now. You know that person’s methodology and you can go straight to business, and that’s what's nice about working with him.”

On a Nolan film it doesn’t feel like you’re involved in a huge movie, Murphy says. Obviously, there’s the scale of the sets, which are awe-inspiring, but on the floor working scenes Nolan is right there beside the actors watching the camera and allowing room for the scene to grow organically.

“However many gazillions of dollars Inception cost he still allows room for us to improvise. He’s lived with this story for 10 years and he knows how every single piece of the jigsaw fits together,” says Murphy.

“So you feel confident deferring to his knowledge of it. All your job is is to find the humanity in it and make the scene as truthful as possible.”

Speaking of working alongside DiCaprio, Murphy is genuinely enthusiastic.

“Chris casts so brilliantly. Everyone in the movie, you can’t imagine anyone else playing their role. He really has a great eye for it,” offers Murphy.

Nolan has cast Pete Postlethwaite as Murphy’s tycoon father, and the two bring an unexpected emotional depth to the film.

“When you see Pete play the father in 'In the Name of the Father' it’s one of the most heartbreaking portrayals of a father ever seen on he screen. It was a huge privilege to work with him,” Murphy adds.

Multi-million dollar budgets, rubbing shoulders with A-listers -- it’s all a million miles from Cork, but Murphy’s accent is unchanged, as is his outlook. Growing up Irish schools didn’t have much room for his creativity, and that hunger has kept his work fresh and his feet on the ground.

“One could say that because in Ireland there wasn’t an outlet for creativity that you had to go and make it yourself. But then if you were given all that opportunity would it become less of a struggle and therefore less important?” he asks.

“I don’t know, it’s a hard one to answer. For my kids I want to give them every opportunity to have creative expression in their education, but does that take away the need to do it? I don’t know.”

The Irish project that everyone’s talking about is Brendan Gleeson’s adaptation of Flann O’Brien’s "At Swim Two Birds." If it happens it will involve every major young Irish male star, including Farrell, Rhys Meyers, and Murphy himself.

“I spoke to Brendan during the year and he’s in the process of raising money,” says Murphy. “I think there’s a huge amount of goodwill toward the film and all of the actors are very much attached and engaged in it.

“It’s a tough time for independent films like this but I feel that it will get made. Brendan is so passionate about it and the script is in such great shape that I feel like it’s gonna happen.”

Meanwhile, Murphy has achieved a rare distinction he’s embarrassed to hear me bring up. An Post, the Irish Postal Service, has put him on a postage stamp, the ultimate form of acclaim.

Was he pleased? “It was nice. I think my granny was pleased with it. It was a thrill for her,” he says. Murphy likes to keep his own opinions to himself.

"Inception" opens nationwide on Wednesday, July 14.