Irvine Welsh is pointing up to the second floor of a grey stone building in Leith, the port district of Edinburgh.
As he gets ready to publish a sequel to his 1993 cult novel Trainspotting, the author is showing me the window of the room, with its view over a local park, where he wrote that first book, which later became a hit film starring Ewan McGregor and Jonny Lee Miller.
The son of a Leith docker and a waitress - who did a course in electrical engineering, spent time in a punk band and was addicted to heroin as a younger man - Welsh had moved back home to Leith from London and "just started typing". He tells me that before writing Trainspotting he had decided "this is my last chance to do something creative".
Trainspotting follows the lives of a group of heroin-addicted friends in Edinburgh. Violent, often shocking and darkly funny, the book is a picture of the social decay sparked by the decimation of Britain's industrial heartlands. It was Welsh's first novel and sold more than a million copies in the UK alone.
But as he sat typing away, back in the early 90s, he had no idea it would do well. "I just wanted to get it done," he explains. It certainly paid off.




