“THESE are really something”, says an amused Graeme Armstrong, as he calls up a couple of pictures on his phone. “I never thought I would see these again”. The pictures were found on someone’s old hard-drive, and they show Armstrong as a 15-year-old, posing with two of his mates. He smiles as he looks at them.

“How many cultural emblems do you need in one picture? The blue Mera Peak jacket, the bottle of Buckfast. I’m quite tanned there; to be fair I think I’d been dogging school for a fortnight before it, sitting in the sun.”

The second picture shows him pulling a face. “I look at myself,” he says with a smile, “and I go, God almighty, what a wee b****** I was …”

To judge from the pictures the teenage Armstrong was just another carefree teen in just another Scottish town. In another, though, he had more than his share of troubles: he had been expelled from one school and been transferred to another; he was running with a gang, and violence was a regular occurrence, and his daily drugs habit was exacting a heavy punishment: panic attacks, anxiety, and a fragile mental health. Not to put too fine a point on it, his future looked bleak.

But he not only survived, he also went on to university – Stirling,in his case, to study English. He returned there to do a Masters in Creative Writing. And now, 13 years after those photographs were taken, he has channelled all of these youthful experiences, which run the full range between euphoria and despair, into a riveting debut novel.

It is called The Young Team, and it crackles with teenage energy, fuelled by the fact that with the exception of a few lines it is written in the sharp tang of irrepressible teenage argot and North Lanarkshire dialect (“We’re aw on a bottle ae Tonic each the night. We see an eld alky stoatin doon the lane in boggin jeans n ripped trainers”).

The C-word clusters over the pages, dense as flies. There are no fewer than 1,400 mentions of it, in fact; but Armstrong points out that the word is merely a term of affection and that that is it how he and his friends really spoke.

The Young Team also looks at the extent to which violence is embedded within some communities. The book’s narrator, Alan ‘Azzy’ Williams, whose gang, the Young Team, constantly brushes up against the Young Toi, observes at one point: “A never really stopped tae feel bad aboot any it, cos it’s just the way things r aboot here. We exist within a culture ae violence. If yi dished it oot this time, yi would end up on the receivin end next time”.

But the book also casts an undeceived eye on life in the margins in post-industrial Scotland, and on the sheer prevalence of drugs in some communities. Some of Azzy’s friends fall victim to drugs; others become dealers.

Most importantly, it chronicles the long, lonely road to redemption for Azzy, whom we first encounter as a 14-year-old. He’s an intelligent, observant boy but he is in thrall to drink and drugs, and is only too ready to put the boot into the Toi. Can his life climb clear, in Philip Larkin’s phrase, of its wrong beginnings?

The Young Team only came out this week but has already engendered a buzz that many other debut novelists would kill for. Nicola Sturgeon tweeted that she has bought a copy, having heard “great things” about it. One Twitter user informed Armstrong: “finished your book mate and coming from a typical working-class male background and growing up in Airdrie in the 00s its one of the most relatable pieces of fiction I have ever read. Hit the nail on the head as far as social realism goes. Future Scottish classic.”

And a number of TV production companies are reading the book with eager interest. “Niven Rennie, the director of the Scottish Violence Reduction Unit, has just tweeted that he’s bought a copy”, says Armstrong, now 28.

Why does he think the book has taken off in the way it has?

“The debate and the key messages that are found within The Young Team are really timely”, he says. “There’s a violence crisis in London, there’s a knife culture that has blown up, and Scotland is being looked at as part of the solution there.

“If you go back to 2004, when there was knife-crime here and we were the murder capital of Europe – within the last 15 years violent homicide in Scotland was reduced by fifty per cent.

“You can say that that’s a cultural shift but I’m sure there’s got to be other drivers as well, and I think the Violence Reduction Unit’s narrative, and the changing narrative about trauma awareness, is part of that. And this” – he taps the book next to him – “feeds into that.

“They get that this is a former gang member who has changed his life and is trying to put a more positive message across”.

The book ends with Azzy seemingly on the cusp of a new life; it’s a tribute to Armstrong’s skill as a writer that despite Williams’s predilection for violence, you are rooting for him at the end.

“People often talk about the end of the book and they ask, what’s the next instalment? Where does he go? I often laugh, and I go back to my own life and I say, I’m still trying to figure that one out.

“I didn’t want to make it this a clean-cut thing whereby he just steals off into the future. It’s a case of, after gangs and that way of life, you need to try to forge a future for yourself. You need to deal with your own trauma, your own mental health, which is poor and had been damaged because of all this stuff, and because of substance abuse as well.

“That’s something I’ve dealt with in my own life as well, to try to move beyond all that: for me, sport and fitness and exercise were a big part of that. But healing and recovery takes a long time. It’s not a certainty in a lot of instances”.

One of the saddest stories in the book concerns a character named Finnegan, once a friend of Azzy’s. When Azzy sees him again after an absence of a few years, Finnegan and his girlfriend are both in a seriously bad way thanks to a serious drug habit, and he has become estranged from his parents, both decent, hard-working types. The couple have just been refused a crisis loan and are in dire straits.

“They’re in an industrial decline”, Williams observes of Finnegan and his girl. “A couldnae imagine wit Connor n Joanne Finnegan [the parents] must be feelin … It wis nae real reflection on the parents, the life we choose fur ourselves”.

“You never see heroin use in the book but there’s a suggestion of it”, Armstrong says, “and I think that point-blank range towards heroin addiction is something that we experienced.

“I was involved with somebody who had taken an overdose. We never took it, heroin was a previous-generation thing, but we were around people who took it – some of our older friends, and friends of friends, died taking it. Three in one year.

“I was 16 at that point, and that was the year I discovered Trainspotting, and that is one of the reasons why the book spoke to me so much. That was one of the defining moments of my life, finding Trainspotting, because it was at that point [2007-2008] there were whispers, if not the realisation, of the economic crash, and our teachers had said to us, ‘If you don’t have a job, don’t leave school’.”

Transpotting was, of course, the groundbreaking 1993 novel by Irvine Welsh, about heroin users in Leith. Azzy Williams has a Trainspotting poster on his bedroom wall.

“I read it ten times, honestly – cover to cover, again and again. I started saying, ‘I’m going to go to uni, I want to read more books’. I was met with healthy scepticism”. This, after all, was his second school: he had been expelled from the first, Airdrie Academy, while in his mid-teens, before transferring to high school in neighbouring Coatbridge.

But he persevered, and he did, indeed, end up at Stirling. Little wonder that he says Welsh’s novel “probably saved my life”.

Armstrong stopped taking drugs on Christmas Day of 2012, more than seven years ago. Isolated, bored, he was sitting in his flat during the first weeks of his withdrawal, and he thought how much he admired Ken Loach’s film, Sweet Sixteen, how it accurately reflected his teenage life and those of his friends. He decided that he was going to write the next Sweet Sixteen, but quickly realised that a screenplay wasn’t for him.

He scribbled down three words on a piece of paper: The Young Team. He looked at them, pondered them, then began writing. By the end of 2015 he had a story on his hands – all 250,000 words of it.

In time, he submitted the manuscript as his undergraduate dissertation. “I was invited back to do a Masters because I had submitted The Young Team as my undergraduate dissertation. They had noticed it and said, ‘This would be perfect for your Masters’.

“Post-graduate studies were nothing I had ever thought about, so I went back, and continued to develop it. Janice Galloway came along as an invited speaker [in 2014 or 2015]. Me and her connected, and she started saying, ‘You need to start submitting this, and get an agent. This is good, this is ready. You’re ready to take the next step’.

“I did 50 to 70 submissions to publishers a year … Realistically, there was no option for me but to keep hitting them. There were a few people interested but it met lots of resistance; it’s gangs, it’s dialect. They thought it was too risky, too hard to understand”.

In the end, it was London agent Jonathan Ruppin who stepped in, last year. He had been looking for marginalised voices, and Armstrong’s was one of the first he came across. He urged him to cut the 250,000 words by 40,000. Further submissions to publishers followed, before Picador snapped it up last September.

The book’s North Lanarkshire vernacular – which, it has to said, takes a chapter or two to get used to – was actually a lot stronger in the original version. Armstrong acknowledges now that it was “almost indecipherable to others”.

It was Janice Galloway who advised him, as she had previously advised Irvine Welsh, to “cut back on the dialect”. Even so, it can take a couple of chapters before most readers of The Young Team will get into the book’s rhythm but it is worth persevering.

At its heart is something that Armstrong said last September when it was announced that Picador had bought his manuscript. “The novel”, he said, “is based upon my experiences of Scotland’s violent gang culture and closely examines our relationship with illegal drugs and addiction. I hope it will offer new ways of thinking and a plausible alternative to young men and women suffering through drugs or violence.”

He is worried, too, about the decline of many Scottish towns, the lack of facilities.

“The full place hud become a ghost toon apart fae the eld pubs”, Azzy observes at one point. “When yir in a modern n vibrant city, this place feels like Bosnia by comparison. Some backwards backwater, in dire need ae resuscitation n life support”.

Armstong believes that towns like Airdrie are “less mobile. There are probably schemes in Glasgow that are similar, but in towns like Airdrie – God, people live and die there. They don’t move on. They don’t have the luxury of a city where they can go and be anonymous. It’s small-town stuff."

As for Armstrong himself, he has moved on. He has graduated from university, has seen his debut novel published by a prominent publisher, and is now working on his next novel. He is set on doing a PhD. “What in? Don’t know. I’m torn between doing a creative one or a critical one. If I was doing a critical one, it would be an exploration of gangs and the social realism of Scotland, and become an expert in a field.

“People sometimes say, would you do something else and expand your range beyond your experience? I think, well, you’re better to actually increase your depth of understanding of literature, of the modern debates around violence reduction.

“It’s a very hot topic,” he continues. “We’ve got a drug-death crisis, and we’ve got a violence crisis in London.” He taps the book again. “This feeds into that. And you should use your artistic and your academic powers to do something if you can. That’s my ambition.”

In the book, a slightly older and wiser Azzy Williams looks back to his carefree years, “when our spirits wur unbroken n our hearts were still on fire”. Those years are depicted with considerable realism; but so, too, is his “lonely road tae redemption”. If anyone can talk about that with first-hand knowledge, it is Graeme Armstrong.

The Young Team, Picador, £14.99.

Graeme Armstrong and Ben Halls, The Young Team and the Quarry Lane Estate, Aye Write!, 12th March 6PM Mitchell Library, Glasgow

Two new writers taking on big social themes.

Twitter @G_Armstrong21