Irvine Welsh’s internationally acclaimed debut novel Trainspotting turned 20 last year. It’s a fact that’s bound to make an entire generation blink. Fans soaked up the Scottish author’s fevered tales of heroin users and their hangers on in and around Edinburgh’s dodgy Leith docks in the 1980s, and it inspired an insanely popular film adaptation starring Ewan McGregor as charismatic rogue Renton, a bleach-blond Jonny Lee Miller as conman Sick Boy and Robert Carlyle as pint-tossing psychopath Begbie.

Welsh is in Australia to promote his eighth full-length novel, The Sex Lives of Siamese Twins, with a trio of appearances at the Sydney Writers’ Festival and a side trip to Melbourne’s Athenaeum Theatre, organised by the Wheeler Centre.

Going to Miami

These days he’s based in Miami, where the new book is set. Largely told from the perspective of two women, Lucy, a sadistic, foul-mouthed and sexually voracious personal trainer, and the reclusive, depressed and seriously overweight Lena, the lives of these women are inextricably bound when Lucy steps in to disarm a lone gunman intent on killing two homeless men. Lena captures the event on her camera phone, casting Lucy as a hero in the reductive 24-hour news cycle.  Lucy takes on the challenge of training Lena, and a decidedly odd and somewhat abusive relationship is formed.

This all plays out against the backdrop of another pair of women filLing the endless news hours, the Siamese twins of the title, one of whom is devoutly religious and chaste, while the other just wants to sleep with her boyfriend. It’s a compelling exploration of our obsession with the body beautiful, and with the emptiness of celebrity obsession.

Normally you don’t give a s*** how you look in Scotland. You get here and when you’ve practically got no clothes on you’re conscious that you’re the guy with the milk bottle skin and the beer gut …

When we speak, Welsh is wolfing down a pub lunch at Sydney’s Criterion Hotel, after enjoying a few days relaxing in the city. Relocating to Miami has had a notable impact on his writing. He admits he’s something of an odd man out in the city’s beach culture. “Normally you don’t give a s*** how you look in Scotland. You get here and when you’ve practically got no clothes on you’re conscious that you’re the guy with the milk bottle skin and the beer gut, so you think ‘I’ve got to go to the gym, lose a bit of weight.’ and all that. It’s really interesting the way you change.”

The characters of Lucy and Lena sprung from his own experience in a Miami gym. “I saw these two women exercising and one really started giving the other one a hard time,” he says. “The other woman burst into tears, and I thought, ‘she’s paying this woman to do this.’ You start to postulate what kind of a relationship might they have? What’s going on with them? It was really interesting to take it from there.”

A prolific Tweeter, while Welsh was working on The Sex Lives of Siamese Twins, there was some discussion on the social media network as to how much he would have to tone down his potty mouth. “They don’t use the term c*** in America,” he says. “It’s the one thing that unites chartered accountants and gangster rappers. They’re kinda horrified by it. So much of the book is written in first person narrative. Neither of the women would use that term, so you can’t have that many c***s in there, as much as I’d love to have loads of them.”

Adaptations

With several of his novels adapted for the big screen, including Trainspotting, Filth and Ecstasy, Welsh has also recently been announced as the screenplay writer for the sequel to Harmony Korine’s Spring Breakers, though neither the director nor that films’ stars, including James Franco and Selena Gomez, will return. Spring Breakers: The Second Coming will feature all new characters and will be helmed by Jonas Åkerlund. Franco took to social media to attack the project on the basis that neither he nor Korine had consented.

“That’s constructed it’s own little narrative with James Franco getting involved in the debate,” Welsh admits. “It was a no brainer. I admired the first film, it was quite an intriguing premise, but we want to do something very different.”

The second coming

There are also high hopes for a big screen adaptation of Welsh’s Porno, the follow up to Trainspotting that regroups with these characters 10 years later. It will also see Welsh re-team up with director Danny Boyle, screenplay writer John Hodge and producer Andrew Macdonald, who will be joined by fellow producer Christian Coulson (Slumdog Millionaire).

“They’ve got a lot of brainpower between them,” Welsh says. “There’s so much energy and enthusiasm. It’s great to be back in the same orbit again. We’ve all worked on different things together over the years but not as a big unit. It’s nice to get the gang back together again.”

Five of the best: Irvine Welsh

Trainspotting, 1993

We’ll be forever grateful for book that gave us Renton, Spud, Sick Boy and Begbie. Though we probably wouldn’t want to meet any of them, there’s something undeniably charismatic about the honest narration of mark Renton in particular, and Ewan McGregor’s yet to top his breakout performance in the 1996 film adaptation. Choose Life.

Porno, 2002

We love those heroin not-so-chic boys so much we relished the chance to check in on them 10 years after the events of Trainspotting.  This time round the heroin dealing’s been replaced by a new moneymaking scheme as the lads dip their dirty toes into the porn industry. There’s still plenty of drug taking, only these days it’s more likely to be cocaine shovelled up their nostrils. Fingers crossed they can get all the guys on board for the proposed cinematic sequel.

Skagboys, 2012

Welsh returned to these characters one last time (probably) with Skagboys, a prequel to Trainspotting that shows us how they ended up in that less than fine mess. The dark shadow of Thatcher’s politics, and the effect that had on working class Scotland, hangs over what is an intelligent insight into a fraught period of UK history.

Filth, 1998

It’s not all about Renton. Bruce Robertson’s corrupt detective and his wordy tapeworm are two of Welsh’s finest literary creations. And by fine we mean really gross, but entertaining. A racist, misogynist, violent monster with too many addictions to list, it’s like literary road kill. He’s terrible, but you can’t help but stare in awe. James McAvoy did a great job bringing him to life in the recent big screen adaptation.

Glue, 2001

With blink and you’ll miss them literary cameos for the Trainspotting boys and even nasty piece of work Bruce, Glue is a cracking yarn about four boys from Edinburgh’s schemes – commission housing – Carl ‘The Milky Bar Kid’ Ewart, Billy ‘Business’ Birrell, Terence ‘Juice Terry’ Lawson and Andrew ‘Gally’ Galloway. Bound by a series of misadventures, some quite horrific, two of the lads will make good, two won’t.

The Sex Lives of Siamese Twins is out now, published by Random House.

For details on Welsh’s speaking appearances, go to www.wheelercentre.com or www.swf.org.au.