I'm not sure whether it's something I actually read, something I heard about somewhere, or something I imagined, but it was a short story consisting of two 'chapters', with chapter 2 being absolutely identical to chapter 1. However, having already read chapter 1 the meaning of everything in chapter 2 was completely different.

I thought perhaps it was by Gabriel Garcia Marquez, Maria Vargas Llosa, Italo Calvino, or somebody like that, but can't find anything of theirs that fits the bill.

Any ideas ?

Don't know, but it sounds intriguing. I would like to read it if you find out.

I've been racking my brains to try and think what the story was about, but no luck. The nearest thing that comes to mind is the movie The Sixth Sense.

Except that with the Sixth Sense you knew you had to re-watch the whole movie, whereas with the short story you didn't realize that chapter 2 was the same as chapter 1 until you were some way into it and suddenly thought, "hang on a mo', I've read this before..."

Of course I remember! This is the story where the hero experiences the same situation twice, but realizes it only in the second chapter. It seems to be repeated word for word, but with each reading you begin to notice new details. If you like such unusual plots, then you will probably enjoy watching interesting films with an unusual structure. 

And the title of the story was... ? And the author ? The reply sounds oddly AI generated to me - but please forgive me if you're a real person ! ;o)

Well seems like some chapters in the Bible are like that. The same story in different locations of the Bible.