Actor Chris Reilly on why working-class roots are his biggest asset

There's been a part in the action-packed TV series Curfew with Billy Zane and Sean Bean (described by Reilly as "a post-apocalyptic death race through London") and four months in Rome filming Devils ("set in the murky world of finance") alongside Patrick Dempsey.

Reilly is among a big-name cast for Official Secrets, led by Keira Knightley as Iraq war whistleblower Katharine Gun, which opens in cinemas next month. He also stars in The Feed, a 10-part dystopian psychological thriller on Virgin TV, which he likens to "social media on steroids".

In recent months, he's shot independent flick, Concrete Plans, amid the rugged Brecon Beacons in south Wales ("a bit Shallow Grave") and sci-fi thriller, The Head, which was filmed in the balmy climes of Tenerife ("think Aliens-meets-Murder On The Orient Express").

Shortly before we're due to meet, Reilly calls – apologetically – from outside the Savoy Centre in Glasgow to say he's arrived slightly early. There's no publicist at his elbow. He's travelled by public transport. Which in this game – the showbiz interview – is a lesser-spotted beast.

Reilly, 41, has a warm and affable manner that belies his self-dubbed tag as a reluctant interviewee. If you recognise the face, chances are you might have seen him popping up in peak time shows such as EastEnders, Silent Witness, Shetland and Call The Midwife.

He rubbed shoulders with Samantha Morton and Tim Roth in drama series Rillington Place and has twice appeared among the star-studded ranks on Game of Thrones (he's played both a Stark and a Lannister). Not to forget a Bafta-winning role as Sergeant Alex Baxter in The Last Post.

A reluctance to rest on his laurels is perhaps due to the fact that Reilly found his vocation later in life. Acting was a pastime before it became a profession – he was 30 before he began pursuing it as a career.

By his own admission, Reilly hails from a tough, working-class background. After dropping out of university in his late teens, he took a job as a joiner helping build a convent in the German city of Leipzig. After returning home to Scotland, he worked on the roads and railways.

There came stints in engineering recruitment and business development before Reilly, by then in his twenties, decided to turn his hand to running a residential homeless unit. As work became all-consuming, Reilly sought a creative outlet. He fell in love with musical theatre – much to the chagrin of friends and family. "My mates used to slag me," he recalls. "Some of my family had conversations within earshot suggesting I had 'come out' because I loved to sing and dance."

After dabbling in amateur dramatics, Reilly honed his skills by learning the ropes backstage at Scottish Opera and Scottish Ballet. "That's how I got my first acting job. I looked up the 'Red Pages' and I saw that a play out of Chichester Festival Theatre was going on tour. They needed an understudy. I phoned up and asked for the job.

"They asked what I had done before and I mentioned some amateur parts. They were humming and hawing, then I said: 'And I can also build your set every single week, so you will be saving money on a carpenter.' That helped sell the idea and I did an audition over the phone. They gave me the job."

Reilly went on to study at the Royal Welsh College of Music and Drama in Cardiff, graduating in 2009, and has spent the past decade growing his body of work.

A star turn in the BBC series, The Last Post, saw off Shetland's Douglas Henshall and Jonathan Watson from Two Doors Down, to win a Scottish Bafta for best television actor last November.

Accepting the award, Reilly made an impassioned speech where he called for better industry access for working class young people, having benefited first-hand himself from a Screen Academy Wales bursary – sponsored by BAFTA Cymru – while at college.

When we speak, it is a point he is keen to reiterate and expand on. "If I could nail my colours to the mast, I believe that the opportunities are out there for everybody. What we need to do is tune working-class kids into the fact they can do it if they want.

"Nobody is stopping anybody from doing anything. I don't think labelling people as victims and telling them they are hard done by does anybody any good.

"Nothing is going to change at the top. There is still going to be nepotism with people giving jobs to their friends or relatives. That is never going to stop. What we need to tell these young kids is that they need to go out there and grab it by the nuts. We need to instil that self-belief."

Reilly is warming to his theme. "We have so many opportunities to be thankful for. We don't live in a Third World country. We have an education system, for all its faults, and we have a health service. We have a route to bettering ourselves and a route to social mobility.

"It might be harder but that is what is going to make you better. I see it as an advantage. Your upbringing and any hardship you have experienced is an advantage. Don't tell me that you haven't got a route to education, that you can't pick up a book or go on the internet.

"Pursue people, write letters, ask for things and take opportunities when they come. I'm not bashing posh people because the way I see it, they are just taking opportunities when they come, and they are ready for them. Fair play to them."

To that end, Reilly credits his own sometimes tumultuous and traumatic life experiences for giving him an edge as an actor. He lays that bare, warts and all.

Reilly's parents split when he was 10 and his childhood was spent largely in the Dunbartonshire town of Alexandria where his father ran a bed and breakfast and worked as a bouncer in a nearby nightclub.

"The B&B was kind of a halfway house, mostly homeless people and social security cheques," he says. "To maximise the income, my brother and I shared a room with an old soldier, the pair of us top and tailing in a cabin bed. When the old soldier was drunk, we would sleep in the living room.

"I reckon that, between the ages of 10 to 16, I must have met hundreds of people with different problems. They were amazing and interesting characters from all over the country."

As a child, Reilly describes himself as something of mixed bag. "I wasn't shy or outgoing – I was somewhere in the middle," he muses. "This is going to sound boastful, but I was academically gifted. I won a load of awards for physics, tech, English and maths. I was good at art too."

Has he ever been IQ tested? "No, but I got the highest grades in the region for my Standard Grades. Then my Highers came along and had a bit of a spat with my stepmother around that time. I totally flunked my Highers. Well, by my standards – I got Bs."

Reilly recounts a tricky juggling act between his own hopes and the expectations of his father, not least with their nightly excursions delivering catalogues to help make ends meet.

"I used to beg to do my homework," he says. "My dad would be in the Volvo with Kleeneze catalogues, me and my brother chasing after him. Three hours a night, I was running around delivering these catalogues, collecting them in, getting chased by dogs.

"I did that every single night after school from the age of 12. I would be almost crying and saying: 'I need to do my homework and study' because my dad would take it for granted that I would get the best marks in school. I was always very small for my age; I was tiny. I didn't hit puberty until I was 19. I was really underdeveloped as a kid but always stocky. I was quite game, though, and would be up for trying anything. I was a bit of an odd kid, but I got on with everybody."

At 16, Reilly moved in with his mother. "My mum was a taxi driver," he says. "She was the first lady taxi driver in Clydebank. She is retired now. She got cancer 25 years ago and it took her leg."

His mother has suffered from ill health in recent years. Reilly was living in London but returned to Clydebank in 2017 to look after her. Asked about their relationship and his face lights up.

"I'm on great terms with my mum," he says. "She really needed some help which is why I moved back. She was diagnosed with pulmonary fibrosis and a complicated condition called Churg-Strauss syndrome.

"The doctor said it was very rare and had been fortunate that they had managed to catch it. She had five doctors at the Queen Elizabeth [University Hospital in Glasgow], and I would regularly see them sitting together over coffee, talking about her because it was baffling them so much.

"Long story short, my mum was given six months to live. But she managed to beat that and was given between two and three years. Then the doctors came back and said she doesn't have pulmonary fibrosis because she is not deteriorating in the way they thought she would. Instead it's an unidentified pulmonary disorder."

Reilly gives an incredulous shake of the head, yet there's no mistaking how his eyes glitter with joy. "So, they reckon she is going to be here in 10 years. Total miracle. Best day of my life."

Having mentally prepared himself for his mother's death, the relief is palpable. "It felt like we beat it together," he says. "It was so difficult. She was waking up every morning crying with the pain.

"I now split my time between Clydebank and London. I have a flat in Stockwell where I stay with friends when I'm down there. Filming Devils in Rome was great because they flew me back and forward to Italy every week."

Reilly chats away about his unusual commute before casually adding: "I'm learning to fly. Maybe soon I can fly myself to jobs." Like John Travolta? "Maybe, aye," he laughs. "Or Harrison Ford doddering into a major airport.

"I'm learning at Cumbernauld. I've done close to 20 lessons and a whole week of flying out in South Africa. I have done my first solo flight. I need to do 45 hours in this country to get my PPL [Private Pilot Licence].

"There is a lot of studying and numbers involved. But it is like anything, if you are relaxed and enjoy it, you retain it. If you are flustered and tense, then you panic. Especially coming in to land."

Reilly has made weighty dramas his calling card but wouldn't mind trying a hand at comedy. "It's about the horse you are riding into battle," he says. "The things I have always got picked for tend to be 'tough guy with a heart' or 'bad guy'. I am keen to widen my casting bracket."

Equally, he has no qualms about turning down roles that don't feel right. "I knocked back the biggest job of my life on a point of principle. I met with the producers from a big American cable company. It was a project turning a franchise into a new series. We got on famously. They loved my ideas and the likeability of the character. Then they offered very silly amounts of money. I asked for just a little more, but they turned me down."

It was, says Reilly, a crucial lesson in the importance of knowing his own worth. "That is a very First World problem. I would imagine anyone reading this will think: 'Oh, you should just have taken it …' But there comes a point where you have to say: 'No, I'm worth a certain amount.'

"It should have been new house money, but it was new car money. Biggest job of my life. Massive. I knocked it back. I did regret it for a while. I sat there mourning my decision for about three months.

"They were insistent that I should value the opportunity a lot more [than the fee]. I probably should have valued the opportunity because it could have been a really big show, but to start off in the American market at that sort of rate would have stopped me climbing the ladder in other projects.

"I did the right thing by saying no, but I mourned the momentum because it is a role that would have injected a lot into my career. I didn't know at that time I was going to get a part in The Head and other projects. I wondered if I had been a little too cocky. Although I knew it was the right decision, it almost felt like I had pissed into the wind and ended peeing on my trousers."

He's since moved on. When we catch up on the phone later, Reilly is upbeat as he talks about filming Concrete Plans in Wales and spending four months shooting The Head – a co-production between HBO Asia and Hulu Japan – in Tenerife.

"Although we filmed in Tenerife, it is set in the Antarctic," he explains. "Being in puffer jackets and warm trousers in that climate was challenging. It has a claustrophobic feel with us being stuck in this ice station, almost like an abyss, and the timeline is fragmented.

"The ice station is doing research that could save the world but then they lose contact for about two weeks. It turns out everyone else is dead apart from two well-hidden survivors who give differing accounts of events. You are kept guessing why and how it happened. It is a cool project."

As for what's next? "I'm going to have some time off," says Reilly. "Working on The Head was hard going. I put weight on, I was drinking because of it. I played an alcoholic and we came up with a system where I could use alcohol as something that would anchor the character. Doing that has taken its toll on my body, so I feel like I need a bit of a rest."

The Feed continues exclusively on Virgin TV Ultra HD, Mondays, 9pm. Official Secrets opens in cinemas on October 18. Follow Chris Reilly on Instagram @ChrisReillyScotland.

Thanks to Clockwise, Savoy Tower, 77 Renfrew Street, Glasgow (workclockwise.co.uk)