Case Histories: Bringing Jackson Brodie to the screen
To be honest, I was so knackered I didn't really feel like throwing myself into creating another series.
But it's such a brilliant novel and Jackson Brodie, the central protagonist, is such a wonderful, complex, beguiling character that I couldn't say no.
For those of you who haven't read the Jackson Brodie novels (what sort of people are you?), they are unconventional thrillers, existing in an exhilarating hinterland between genre and art. And they are unputdownable.
As a screenwriter you're always looking for challenges, something to pull you out of your comfort zone, and it quickly became clear that I'd taken on a massive job.
Every other person I mentioned the book to adored it, especially women, and had very strong feelings about who should play Jackson Brodie and what the series should look like.
No pressure, then.
But first I had to meet Kate Atkinson.
Nobody was as crass to mention it, of course, but this was sort of an audition for me.
As I knocked on Kate's front door and marshalled my thoughts I realised this is how actors must feel a lot of the time.
Note to self - be nicer to actors.
So Kate and I strolled around Edinburgh in the rain, talking about her characters, where they might live and eat and drink.
Case Histories is actually set in Cambridge but, as we were adapting three of the books and they're each set in a different place, it was clearly going to be necessary for us to decide on one city and try to make it a character in its own right.
I plumped for Edinburgh, not because Kate lived there, but because it has such a wonderful Gothic presence that I felt would fit perfectly with Kate's form of skewed realism.
I loved writing the scripts. The heavy-lifting had already been done by Kate - the characters, the story, the tone - so my job was to smash up the novel and re-imagine it as a screenplay. A fresh mosaic.
I decided to curve one story over two episodes, to give each two-parter a strong structure, and then largely play out separate self-contained stories in each episode.
It meant that the films wouldn't have the relentless, restless narrative that you often get on TV in this genre, but could meander through murder to domesticity, from comedy to tragedy.
The books always struck me for their very grown-up sense of sexuality and disappointed hope.
The structure gave us the chance to do justice to that - to sometimes sit back off the main thrust of the story and explore Jackson's life and past a bit.
It's always a privilege to spend time with other writers' characters and works, living or dead. It's not for the faint-hearted.
I know there are armies of Atkinson fans out there who have their own utterly perfect version of Jackson Brodie in their heads, and who will curse me for fiddling with perfection.
But what joy, to take tea with one of our finest living novelists in a damp cafe in Edinburgh and talk about writing. What could be better? A beer with Thomas Hardy?
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Comments made by writers on the BBC TV blog are their own opinions and not necessarily those of the BBC.