It’s just after 9am on January 15, 2017, and an early-rising Irvine Welsh is staring bemusedly out the window of the Chicago apartment he shares with his American second wife, Beth Quinn, as he takes this call from Hot Press. Usually at this time of year he’d be facing a blindingly white vista of snow and ice, but apparently the weather in the Windy City has been quite erratic of late.

“It’s been a funny old winter,” the 59-year-old writer and filmmaker muses, speaking in a strong Scottish accent. “At this time of year it’s normally so cold and snowy and icy that you just can’t go out, and so you hole up and get things done. But it’s been quite strange. The temperature is all over the place; it’s gone up into the fifties again this weekend, so it kind of feels like it’s gone back into autumn. We’ve gone backwards. It’s bizarre.”

It’s probably just all that hot air from Donald Trump…

“I think that must be what it is,” he chuckles. “He’s such an asshole.”

Whatever about the weirdness of the weather and the political climate, Welsh sounds in chipper form. He’s on the line to discuss the long-awaited sequel to iconic 1996 movie Trainspotting, which was adapted from his skaggy 1993 novel of the same name. Shot last year on location in Edinburgh on a budget of €15 million – ten times the money spent on the original – and loosely based on his 2002 novel, Porno, the rather clunkily titled T2 Trainspotting reunites all of the same cast and crew of the film that, for many, defined independent British cinema in the ’90s.

All the old hands are on deck. Danny Boyle has directed, John Hodge wrote the script, and Andrew MacDonald produced. Meanwhile, in front of the camera, Ewan McGregor, Jonny Lee Miller, Robert Carlyle and Ewen Bremner have reprised their respective roles as Mark Renton, Sick Boy, Begbie and Spud. Having made a cameo as a heroin dealer in the original film, Welsh reportedly makes another appearance in this outing.

Hot Press hasn’t seen the movie yet, but expectations are high. Almost as high as the main characters…

OLAF TYARANSEN: How hands-on were you in the making of T2 Trainspotting?

IRVINE WELSH: I think as a writer you’re not really involved in the making of it. It’s a kind of process where all it takes in the making of the movie is they shoot and they edit, basically. You’ve done stuff and then you actually put it together. But the biggest part of anything like a book or a film or whatever, is the preparation. And as a writer, you’re not really on set that much because you wouldn’t be given that much to do. Especially if you’re really the second writer, because John [Hodge] adapted the screenplay. So I wasn’t really that much involved on the set. But, I mean, I have been involved with the whole thing about getting it together for the last 15 years. We all have, so when you actually get to shooting the thing, it’s just euphoria, it’s like a holiday. You’ve done all your work, basically, all your preparation. You’re really trying to realise that, and that’s Danny [Boyle] and that’s Anthony [Dod Mantle] the cinematographer, they’re doing the whole thing from then on in. But most of the work probably came from Danny as well, definitely from Danny. It’s all in the preparation, you know, we’ve taken a long, long time to prepare for this one.

Porno was originally published in 2002. How stop/start was the process of adapting it for the screen?

There were a couple of times when I did think it was gonna come together. The first was just after the book had come out, and John had a script, which was really good, and I think it would have been a great film. But it would have been a film very much of that time, we couldn’t really shoot that now in this age, because things have changed so quickly – especially stuff like the gonzo porn scene. We’ve talked about this before, Olaf. So I think, eventually, that stuff couldn’t get done for various reasons.

T2 features the same cast and crew as the original Trainspotting. Was it difficult reassembling that team?

Yeah, that was the biggest thing. I mean, there’s all these actors and everybody’s been involved in different projects on the way, but the craziest thing about it is, it’s just a lot of people to get together at one time, you know? Especially because they’re all in demand now, and they’re all working on other things. Not just the actors, there’s our screenwriter, director, and all that, they’re all committed to long-term projects. I’ve got deadlines myself and all that. So, getting everybody together was a difficult thing.

So how did it happen in the end?

We got to a point maybe about four years ago where we decided that it really had to happen; it was getting up to the 20th anniversary, and it was now or never: “If we don’t do this in the next few years, we’re not going to do it at all.” That sort of lit a fire under us, and we went back to the old script, but we couldn’t do it as it was. We had to try and find another way, to make it more contemporary. You don’t want 45-year-olds playing 35-year-olds and pretending that they’re living in the early 2000s and all that. It’s just not satisfying to do that. So we pressed on, we got together about three years ago, and just spent some time hanging out at a house in Edinburgh.

You all lived together?

Kind of. We went out and met with lots of people, chatted with lots of people in community groups, you know, people that I knew, and did some daft stuff and all that. We went to the Boxing Club and hung out there. We made food for each other like in the Big Brother house, and we went around restaurants and stuff like that. We had a great time, cooking up together and getting to know the city again. And the script fortunately came out of that, which kind of lit a fire under the actors, and it was all systems go from there. It was really spending that time together, enjoying coming out with that script that got the whole ball rolling again.

Were you not tempted to write the script yourself?

No, no, you don’t fuck with something that’s working. I mean, there’s a great alchemy there. One of the reasons why it’s taken so long is that I was insisting that it wouldn’t happen without the same people. So I wanted the same director, the same producer, the same screenwriter, the same four lead actors and anybody else we could get was essential to it. And we got the same crew involved. And to me, you do it that way or you don’t do it at all. I mean, there’s loads of people that wanted the rights to Porno to do as a sequel to Trainspotting. I could have cashed in for big bucks.

Were you not tempted to just take the money and run?

Yeah, I was tempted on a few occasions, but I stuck to that idea of it having to be the same people. And I think everybody felt like that, too. I know that Danny would never have shot it without these four guys in the principal roles, and I know that Andrew wouldn’t have wanted to shoot it without Danny. John understands that world cinematically better than I do. He understands all these characters, and he knows how to get them so these characters are gonna work on screen. He has all that energy and all that talent from the first movie, and I just wanted to replicate that as much as possible.

Obviously I haven’t seen T2 yet, but is it intended to reconnect with the original Trainspotting audience or is this aimed at a new generation?

It’s both, really. It has quite a lot of references to the film, you see some old stills from the original that weren’t used in flashbacks. Which is really interesting and very emotional, so it does have that connection to Trainspotting. But it’s very much a film of now, a film about how for the past 35 years people have really been struggling and hustling to get by, and maybe have had just the odd moment of a little place in the sun. But it’s about that whole phenomenon of how we find it almost impossible to grow up, and to grow old. We grow old physically, but mentally, we still hang on to the culture, and youth culture’s become kind of mainstream culture now, we’ve all gone to that whole sense of ourselves. And sometimes there’s a lot of fun to be had in that, and it’s quite emotional, and quite sad, but in other things, it’s quite uplifting. So it feels like a much more layered film than the original one, but it still moves at a very fast pace with all these action sequences and comedic sequences. So it’s very much like the first movie, but a lot more emotional, with a lot more layers to it.

You had a cameo in the original movie as heroin dealer Mikey Forrester. Does he make a reappearance in T2?

Yeah, Mikey Forrester’s back and he’s the only guy who seems to have done well (laughs). John kind of wrote Mikey Forrester up as a more successful version of where I’d last seen him. John’s got me in this massive lock-up warehouse buying and selling all sorts of fantastic merchandise. So I had no complaints about going up in the world.

The soundtrack was leaked online last week…

Yeah, it’s officially out there now. We got loads of absolutely fantastic music to put in. But it’s not like Desert Island Discs, it’s not like your favourite track of the day, it’s the ones that are gonna help tell the story. So there’s a lot of great music that we couldn’t use, and we’ve got a soundtrack that is really quirky and fun and eclectic, but it really is what the film is about, basically. It really sums it up.

The Rubberbandits ‘Dad’s Best Friend’ is on there…

Yeah, you’ve got fun stuff like the Rubberbandits, and old stuff like Blondie and Queen, which are quite anthemic and sum up the guys’ journey. You’ve got stuff like Underworld and Iggy Pop and all that, they’ve all been redone in a modern kind of way. And you’ve got Young Fathers, who are the quintessential sound of the whole film. Danny was blown away by these guys, their music and their attitude, and he says, “This is the sound of Trainspotting 2,” basically. So you have that very Edinburgh sound. Edinburgh in the world is a sort of multicultural force. You have all these things coming together, and to me, they are the whole spirit of the film and what it’s about.

Weren’t Oasis asked to contribute, but Noel Gallagher refused because he misunderstood the request and said he didn’t want to feature in a film about trainspotters?

You mean back in the original film? Yeah, I’m not sure about that. We had a lot of great stuff, a lot of great bands, we had massive bands. I sound a bit like Donald Trump now (laughs). We had the HUGEST bands! We had the HUGEST names! But we went for the karaoke kind of tribute guys instead, got to give them a chance. THEIR SALES ARE GOING THROUGH THE ROOF!!!! But we had a lot of massive household names deliver fantastic tracks. I suppose Queen are a massive household name, and they put a little track on it. But again, it’s supposed to fit the movie. When you listen to the first soundtrack album, it’s a great record with some great tracks on it, but it would make no sense at all if it wasn’t for the movie. If you sat down and listened to the album, you’d think, ‘Oh that’s a good track, but what the fuck are they all doing together? What is this all about?’ But the movie contextualises it. If you play that album, you can anticipate the movie. But once you’ve seen that movie and you play that album, it’ll fucking shoot for the stars. The two plus two equals 500 effect!

You’ve written two subsequent novels featuring the same characters in Skagboys and The Blade Artist. So are you already thinking about doing Trainspotting 3?

Well, I’d be lying if I said it hadn’t crossed my mind recently, because I’ve been writing more about these characters again. It’s the result of talking to John and Danny about them for the last four or five years. It’s put them right back on the map. I don’t think I can rule it out as a possibility. Andrew and I have been talking about doing Skagboys as a TV show, we can maybe go back into the history of the guys, and get new younger actors taking us back through the genre and redoing the whole thing in a very different way. But yeah, we’re excited about the possibility if it opens up. Then again, if you’re a writer and you can’t get excited about things then you shouldn’t be writing. And I get excited about everything. I’m excited about Las Vegas right now. I’m absolutely fascinated by it and by the idea of writing a Vegas novel.

What have you got coming out next?

Dean Cavanagh and I have been working on some movies. We’ve got Nick Moran directing the Alan McGee Creation biopic. We’ve got another sort of heist movie which we’re developing, we’ve got the script and we’ve got directors and we’re moving on with that. So those two things are quite big ones. We’re also working on Crime as a TV show, we’re dramatising that for television, that’s going ahead. I’ve got a couple of novels that I’ve been messing around with for a couple years or so, so I’m hoping to make progress on them. And then there’s a play in Chicago, a musical, kind of pop opera, which opens next month, which is quite scary because we’ve got so much work to do. That should be fun to, it’s a workshop kind of project, we’re basically developing it live in Chicago, which is a fantastic space. So that’s exciting, because it’s a music-based project, and everybody relates to music, you feel like you’re involving the whole community in the development of it. People can come out and they can leave comments, they can join the actual workshops that we have with the actors. So it’s quite fun. A Chicago writer and myself are writing it, but you’re still getting all that input from different people. It makes for a very fun project to be involved in.

I don’t know how you find the time.

Clean living, mate, that’s all that is (laughs).

Finally, you’ve mostly been based in America for the last few years. What are your thoughts on Trump’s election?

I think something’s probably got to give, really (sighs). I mean, I’m looking at all the news channels and all that, and he’s not even in power yet, and it’s like there seems to be a massive ongoing war taking place. It’s not taking place on the streets, but it’s taking place in every kind of... it’s all people are talking about. It’s the sort of subtext for everything, and it seems to me to invite a kind of paralysis in the whole system of government. I don’t know. I mean, I think that it’s inevitable when you produce such a controversial candidate. Everything seems to be contested now, every single thing. And he’s not even in power yet, so it’s gonna be an absolute battlefield here, psychologically and culturally, over the next three or four years. There’s so many skeletons in this guy’s cupboard, I can see so many legal challenges. I don’t think he expected to win, and he’s not equipped for it. What he’s got in his businesses, and his private life, and his stuff with the taxes and all the money that he’s owing, I think he wants to keep that hidden, and now he’s gonna have all these legal challenges to expose it. There’ll be a lot of courtroom brawls and paralysis over the next few years. I expect to see him go from this victim/bully thing, back and forth, back and forth, because that’s his psychology. It’s gonna be such a strange thing to have somebody like that right at the head of the government. From my point of view, and for artists and writers, it’s massively exciting, because you’re looking at something that’s got the potential to be a major disintegrating factor in the whole society, really. I suppose from a citizen’s point of view it sucks, but from an artist’s point of view it’s fucking great (laughs). T2 Trainspotting is released on January 27.