It's the end of an era.
After 70 episodes and more than two decades of playing Agatha Christie's Belgian sleuth, Hercule Poirot, David Suchet has hung up his hat as one of the world's best loved detectives.
Acclaimed playwright Nick Dear, the man who penned Danny Boyle's version of Frankenstein (with Benedict Cumberbatch and Jonny Lee Miller) for the National Theatre, knows the character better than most, having adapted six of Christie's Poirot novels for the small screen.
I spoke to the fiftysomething writer, and wondered how hard it was bringing one of Christie's best loved creations to life for a 21st-century audience.
Were you familiar with Christie's work when you started on Poirot?
Not at all. I was first approached to do it in 2002 I think.
No, I couldn't say Agatha Christie was very high on my reading list. I thought I was much too much of an intellectual for that. I'm now prepared to accept that I might have been too much of a snob because after a dozen years of being associated with the shows, because I have written six of them now for ITV, I think it's very classy entertainment and I'm pleased to be associated with it.
What is it about Poirot in the books and on TV that attracts so many fans?
It's very hard to pin down, because no one can ever quite second guess the secret of success. If we knew what the formula was, we'd repeat it over and over again.
"One of the reasons these stories are enjoyed it is because she (Christie) creates such wonderful galleries of characters for each show. They're slightly eccentric, but very often recognisable."
There is an assumption that Christie only ever deals with the upper class; it is quite wrong. She is very often dealing with pretty ordinary people, and every now and then with what we call the lower classes, so it's wrong to suggest they are all like aristocrats in that kind of PG Wodehouse way.
"People enjoy it because they like the idea that beneath this veneer of respectability there are very murky goings on."
In most of the stories, the proposal is of a world that we recognise in which people behave appropriately and politely, and then very quickly discover that beneath that surface there's all kinds of mayhem.
That was very true of Christie's own life, in that she had a very messy divorce in the 1920s and suddenly found herself alone as a single mother with very little income apart from what she could make from writing.
"We have this image of a very, very conservative person which in later life she certainly was, but she had a fairly feminist attitude and she's stuck out and said 'I'm going to be a writer. And I'm going to make my living', and she worked like a dog, and was very successful."
Which is your favourite Poirot adaptation?
It's my final one (Dead Man's Folly), because we got to shoot it down at Agatha Christie's house outside Torquay. Most of the film is shot there in fact; it is now owned by the National Trust, it was her holiday house, this grand Georgian pile.
After negotiating with the National Trust and Agatha Christie's grandson, Matthew Prichard, who is the chair of Agatha Christie Ltd, we got permission to shoot there because this book, the geography of the book is actually based on her own home.
The crime is set during a garden fete. So to shoot it in the place where she set it and actually lived... I went down there for a couple of days in the summer when they were filming. It was a very curious meta fiction if you like. A fictional character arriving back at the real place where he was invented.
What are the crucial elements of adapting Agatha Christie's work for TV?
To a degree we are looking to 'modernise' the glamour of the story if you like. Not to update it. Poirot's stories are written between 1924 and 1972 is the final one, believe it or not.
There's been a stipulation from ITV, who always produces it, they're always set in the 1930s. So no matter when they are written, we have to set them in the late 30s, just for that style thing that people like so much.
I say modernise, I don't mean update the story, I mean update the grammar, and sometimes the pace.
I think that audiences change decade by decade in a way. If we look back now at the first ones that David Suchet did 25 years ago, you will see a much more jaunty character. Much more flippant about the crimes.
"Nobody ever grieves for a minute in Christie; 10 seconds of grief, then it's onto the next murder. What we've done with them in the last 10 years is make them rather darker, existentially bleaker, and have Poirot faced sometimes with very difficult moral choices."
When I say bring them into the modern world a bit, it's trying not to make them look dated. They are all set in the 1930s, but we try and keep them at the speed that we like to watch TV now.
David Suchet's tenure as Poirot is over, but would you like to work on a big screen version?
I'd consider working on anything that I'm asked to work on. In some ways I'm a writer for hire. I've made my living at it for 30 years. People come along and offer me a job, I looked very hard at it.
Different actors have played Poirot before, and I expect different actors will play him again.
My guess would be that the brand would lie low for a while, and then might make another appearance.
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