‘I THINK we’re all vengeful,” says Irvine Welsh as we meet in a café in Edinburgh’s Canongate. Fuelled up on caffeine, he is ready to embark on the book tour of the final instalment in the Crime trilogy.

In Resolution, former DI Ray ­Lennox is determined to get a fresh start. In Brighton, he finds himself a new career path and a girlfriend 15 years younger. She introduces him to a rich property developer whose face looks oddly familiar. And as he ­investigates the disappearance of ­foster boys, the recovering drug ­addict is doomed to face the trauma of his past.

In Resolution, Welsh offers Lennox his redemption – as readers wonder if the former cop finally found his predator.

“I wanted to make it a bit more out there and have a supernatural element with the predatory guy that he’s trying to track down. I wanted to get to that point where him and the reader didn’t really know if he was abused by this guy or has he just gone crazy?” explains Welsh.

After the novel Crime was adapted for TV, Welsh was asked for more. During lockdown, he wrote two other books – The Long Knives and ­Resolution.

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Throughout the series, Lennox is driven by an increasing appetite for vengeance. A trait Welsh believes all of us are ultimately guilty of.

“I think we’re all vengeful. If ­nobody believed in revenge, or ­vengeance, you could sort out the Middle East in 10 minutes. But the cultural pain that we take down the generations kind of stays with us.

“The need for revenge is often ­displaced into somebody that’s ­weaker rather than somebody that’s caused you problems in the first place. It’s one of the unfortunate characteristics of human beings,” he says.

In his books, often described as dark and gritty, nothing is off the ­table. But Welsh’s intent is not to shock, but rather expose societal pressures – and the mistakes they can lead to.

“When people are under real extreme pressure and they don’t have a lot of social ammunition to cope, they just act impulsively and make mistakes.

“I don’t really have anything that’s off limits, but I don’t set out to write about something that’s shocking. I like to get people in a room that are gonna spark conflict with each other.”

The Prime Minister Keir StarmerThe Prime Minister Keir Starmer

Welsh’s characters share opposite and rather extreme views on societal issues. After a swinging victory from Labour in the elections, one might wonder what Lennox would have thought of the results.

With a slight smile, Welsh offers: “When you don’t really think about a character in that context, you just end up thinking of what you thought about it. So, I think he would be quite cynical about the election.”

According to the pro-independence author, there is no loyalty to parties any more.

“Things are so volatile, the ­majority they have could be wiped out in five years time. There’s no loyalty to ­parties now, everybody’s living on borrowed votes.”

Could it be a case of choosing a lesser evil?

Speaking of the ­election results, he says: “What they’re saying is ­basically ‘We’ll have ­exactly the same policies as the Tories, but we won’t be ­corrupt. We won’t be able to spend taxpayers money on yachts for our friends, and we’ll try and get some of that back for you’, and that passes as idealism now.”

In his novels, Welsh often flirts with the grey areas of morality, where anti-heroes reign. To an extent, he says we’re all in a grey area – one where it’s “hard for people to act in a moral way”.

“The way the world is set up, you’re either forced into being a ­total ­bastard or a real mug, basically.

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“There used to be a big space ­between the two where you could be a human being. Now we’re in this ­terrible ­situation where everybody’s a member of the precariat.”

He points out even somebody ­doing really well could be out on the streets in a couple of months – and that there’s a “hierarchy of beggars”.

“You’re seeing the rise of the ­hipster jakie on the Tube, the guy’s ­doing these PowerPoint ­presentations ­going ‘I’m really sorry, but I’m not an ­alcoholic, I’m not a drug addict, I lost my job’.

“Everybody in the Tube just give them money. But out of the Tube, somebody is sitting there, shabby and destitute, and they’re not ­interested because they can’t relate to ­something like that – they’re too far gone.”

A scenario in which Welsh can ­imagine Keir Starmer – and the role he could play.

“Where you have the local ­councils, like Keir Starmer, I can see him in Camden Council going ‘Let’s have presentation skills for homeless people, you have these guys teaching bums how to kind of beg’. The ­horror of it, food banks and everything, they’re all incorporated into this new liberal system, it’s just absolutely crazy.”

His cup is now empty, and he switches to tea, as he fears he might end up drinking coffee all day – the perks of a jam-packed book tour.

Ewan McGregor in Trainspotting

Despite prolifically voicing his thoughts on X, Welsh does not ­engage in online debates, but admits he often takes the “contentious” route.

“Why would you want to argue with somebody on Twitter? It’s stupid, nothing is going to be established or proven by it. The only reason I do it is to try and say something contentious, build up followers, and then when I have something come out, you’re just thrusting a leaflet into the hands of 350,000 people,” Welsh says.

He certainly isn’t the only one who has no interest in debating on social media.

“I think a lot of people are getting to that point. It’s not real life, not real debate. It’s going to take a few years, but I think people will start going out again and they’ll start interacting properly,” he says.

The author questions whether change is irrevocable in a post-industrial world.

“People obsess with identity and you think, is this just a product of mental illness? Or are we genuinely in a post-industrial world where the ­vision of labour and all the sex and gender roles, is changing ­irrevocably?,” he ponders.

He doesn’t really know, but either way, Welsh is fascinated.

“It’s such an interesting and ­exciting debate. I don’t really know, but it’s something that does fascinate me. The problem is that it’s taking place on social media, where you just have people shouting at each other.”

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Over the years, Welsh has had his fair share of controversy. In 1993, his novel Trainspotting was pulled from the Booker Prize shortlist after judges threatened to resign over its content.

In 2020, he approached ­cancel ­culture in his documentary, ­Offended. One could wonder – has he ever fear being cancelled?

“I think probably back in the day when they took me off the Booker shortlist. But I think that did me a lot of good as well.

“A lot of older ­people who have been ­successful ­artists moan that they’ve been ­cancelled ­because they’ve got quite old and ­reactionary. You’ve not been ­cancelled because of that thing you’ve said that’s edgy, you’ve just been cast as if you were a boring old c***t.”

Last month, Welsh briefly shared his thoughts on trans rights in an ­interview.

“Only women and trans people can have that discussion, but what I would say is that I don’t ­believe trans rights should be advanced at the ­expense of 50% of the population,” he told The Times.

Comments that surprised many of his fans, perhaps even more so after his novel, The Long Knives, featured multiple transgender characters.

For both the book and its TV ­adaptation, Welsh worked with a ­sensitivity reader – a process he would recommend to others.

“Something that’s as alive and as dynamic as that issue, you can’t keep up with it. You have to have someone who’s had that lived experience, it’s an aid to research, you can’t see it as a censorship tool. The trans advisors were very much ‘Write what you like, but here is actually the reality of it’ –and you have to take that reality into account.”

Last year marked the 30th anniversary of Trainspotting. Even though the “King of the 90s” is now in his sixties, his audience seems to get younger.

“I think it continues to resonate with people because it’s about a ­transition to a world without paid work, that’s what the characters are struggling with. It used to be the ­post-industrial working classes, now it’s everybody.

“Every time I do readings, it’s like the audience gets younger and I get older. When I first started, there were peers, old punks and ravers. Now, it’s their children and grandchildren that discover the book.”

On the table lays a copy of Resolution, brought by this reporter. Welsh admits if they heard what he said next, his publishers “might go nuts”.

“I’m supposed to be promoting it, but I don’t really care about it any more. I’m only interested in the book I’m writing now.”

Speaking of his next project, he says: “My idea is to write a book about men in love and to write a ­disco album at the same time and they both come out together.”

As we are both caffeinated and about to part ways, I ask: “Is there something people might be surprised to know about you?”

“People always say to me, quite shocked, ‘You’re very tall’. I don’t know why that is, maybe you always think that people that write books are going to be short,” he laughs.