It’s twenty years next month since Trainspotting the film was launched in Glasgow. Do you remember it? Were you there? When was the first time you saw it? Subversive and insolent, it was ruthlessly marketed as a consumer item: the best of both worlds! Does it tell the truth about the world of junkies? Yes, it does, but it massively misrepresents it as well. Look at the over-dose scene – there never was a dealer who stood by a comatose user whom he had just supplied, seeing him into a taxi and paying his fare to hospital. And the ending – is it not as corny as a western?

I’m giving a talk at the Edinburgh Central Library at 2.30 on Wednesday 17 February. Tickets are free, so visit http://www.eventbrite.co.uk/o/edinburgh-reads-1650684470 and come along, it will be nice to see you.

My chapter on the film, now at the stage of final drafts, takes advantage of a two-decade perspective. And I have a completely fresh take on it which commentators and critics have missed. There are some major and some subtle changes from Trainspotting the book; they are related, of course, and yet very different. There’s plenty to explore and discuss.