Irvine Welsh: ‘Everything has become so shouty’

Irvine Welsh, 63, grew up in Muirhouse, north Edinburgh, and lives in Oxfordshire, having spent most of the 2010s in Chicago and Miami. The Long Knives, his 13th novel, is a sequel to 2008’s Crime, which screened last year as a six-part BritBox series with Dougray Scott in the lead role of DI Ray Lennox. In the new book, Lennox is tasked with solving the murder of a Tory MP found castrated in a Leith warehouse. Welsh spoke as shooting was about to begin on its television adaptation; other business in hand included Trainspotting’s forthcoming debut as a West End musical, two separate documentaries about his life (“like buses, you know”), a recently launched record label and getting married for a third time.

Did you always plan to write a sequel to Crime?
Doing the TV show [of the first novel] piqued my curiosity. We were telling the story about Lennox’s family and this thing that happened to him as a kid, and since it was doing well and there was a chance for another season, I wrote about what would happen if he found the guys who abused him. But the novel I wrote then will be coming out next year, because it seemed to leave space for another book in between to develop the family drama and really set up the payoff. I thought if I could get it done in time, the show’s second season could be based on The Long Knives instead and it is. So having not had a book out since 2017, they’re now coming thick and fast because I did nothing in lockdown except write.

What led you to the novel’s transgender storyline?
I just thought it was such interesting waters to go into. We’re all asking fundamental questions about identity now that the things that defined us are slipping away. It’s complex, moving-picture stuff. You don’t know how much of it is a distraction to keep us at each other’s throats politically: if trans women compete in athletics, or if they’re barred, it’s not going to change the fact that lots of people are going to die because everybody’s getting fucked with their heating bills over the winter. It’s obviously difficult waters to go into because everything has become so shouty. We had a trans adviser on the book and I was dreading it. I thought, this is going to be another layer of censorship. But it was incredibly educational. I learned a lot.

Did anything change in the book?
Certain things did change. There’s certain things I just got wrong; I’m happy to be corrected. Other things [other responses] were quite affirmative. It was nice to have the motivation for what I was doing understood.

What draws you to sexual abuse as a theme in your work?
I like to challenge and annoy and disturb and irritate the fuck out of myself when I write. That’s really the motivation: to push myself to look at things that aren’t looked at in fiction, or get looked at in a very trite way from the godlike position of the author, rather than from the point of view of the people actually involved, who often get reduced to barbaric simpletons with no roots to their behaviour.

Yet, like most of your recent novels, The Long Knives is a comedy of sorts.
I tend to use humour to give the reader a break. If you’re forcing people to look at potentially intolerable material, you have to give them space to reset; you can show as much darkness as possible as long as you’re groping in some ways for the light switch.

Plot didn’t always drive your fiction the way it does now.
No, I’ve learned how to do that down the years. I didn’t know how to write a novel when I wrote Trainspotting. I had these loose stories that seemed to be heading somewhere; the start was going on too much about how they became junkies, so I cut it and went straight into their world and ended it with a heist ending I thought would be dramatic. Then I went on to The Acid House – more stories. Marabou Stork Nightmares was my first attempt at a conventional novel but it turned out quite experimental. I was just messing around in those first few books. They were probably the best ones, because then you learn how to write and you end up writing like everybody else [laughs].

The story goes that Trainspotting stood to be Booker-shortlisted in 1993 until two judges threatened to quit. Do you ever think what might have been?
Probably what might have been is that it might’ve been shite. I can’t think of a working-class British writer who’s done massively well out of winning the Booker prize; it didn’t do [James] Kelman much good.

What have you been reading recently?
The latest in The Secret DJ series, which I really like. I’ve been DJing again compulsively this year and it’s just DJs talking about how they got into the business. I’ve just finished Rachel Ingalls’s Mrs Caliban, which I enjoyed – it’s kind of weird and cool. The other thing I’ve been enjoying is Stéphane Mallarmé’s Collected Poems and Other Verse [in an Oxford World’s Classics translation by EH and AM Blackmore]. I can’t read French and I love the way it’s got the French on the other side with the English.

Which novels inspired you?
Evelyn Waugh’s Sword of Honour trilogy influenced me a lot; even though the characters had a completely different background to mine, I found the psychology of male schadenfreude and competitiveness really well observed. A background pulse [to wanting to write] came from the big Scottish books that made everyone go, whoa, this is great: William McIlvanney’s Laidlaw, Kelman’s The Busconductor Hines, Alasdair Gray’s Lanark, Janice Galloway’s The Trick Is to Keep Breathing. But a lot of my stuff just comes from listening to people shouting at each other in queues, in pubs, on buses; I don’t drive, so public transport is a really fabulous place for me to pick up references. When I was taking the elevated subway to baseball games in Chicago, you’d hear people rapping with each other and I’d be translating it into Scottish, thinking, well, this is how people would be talking if they were going to Tynecastle or Easter Road or whatever.

Are you ever tempted to write an autobiography?
I’ve got two documentary crews following me around, so the last thing I need is an autobiography. To some extent you have to be an egotist to be any kind of artist at all, but I’m not really interested in looking at myself from the outside. My wife says: “You’re just weird; you’re an alien, basically” and I don’t really want to show the world my fucking weirdness, you know? These things sneak up on you, though. Like, you’d always think Trainspotting would be a very autobiographical novel and that something like The Sex Lives of Siamese Twins, with these two much younger female American narrators, would be different. Then when my ex-wife read it, she said: “These characters are more like you than any other character you’ve ever written in your life.” You don’t realise that when you write you’re always bizarrely outing yourself.

• The Long Knives by Irvine Welsh is published by Jonathan Cape (£18.99). To support the Guardian and Observer order your copy at guardianbookshop.com. Delivery charges may apply