Sophie Hannah, author of the new Hercule Poirot mystery The Monogram Murders, shares how she channeled one of literature's greats, and one of literature's great characters.

Since it was announced last September that I would be writing a new Hercule Poirot novel, I have read many accounts of what I intend to do to the poor Belgian detective that bear no resemblance to the truth. Am I going to ‘resurrect’ him – from the dead, as the word implies? Absolutely not. Agatha Christie killed him in Curtain, and that’s that; he can’t and shouldn’t be brought back to life. Am I going to ‘revive’ him, then? Well, no. Insofar as he’s dead, he can’t be revived, and as a fictional character, he is still going strong: eternally popular, world famous, and in no need of revival.

So, am I, perhaps, going to ‘update’ him? Heavens, no. Poirot is a classic character from fiction, not a MacBook Air; he would not benefit from updates. What about ‘recreate’, then? No again. His inventor created him so well that there is nothing to add. We all love (and are intermittently infuriated by) Poirot just the way he is.

What, then, do I intend to do to Christie’s detective in my novel The Monogram Murders? The answer’s simple: I’m going to write about him. That’s it – nothing more and nothing less. I’ve created a policeman character, Edward Catchpool, who is Poirot’s sidekick for the duration of my book, and he is the narrator of the story. He writes and talks about Poirot as someone who has come to know him well. I chose this approach because I decided it would feel natural and authentic (since I too am someone who has come to know Poirot well), and it did. It seemed the best and least appropriative way forward.

I have invented a case for Poirot to solve and a sidekick to help him. I’ve provided murders, suspects, motives, clues, twists, and I’ve even thrown in a posh London hotel and a beautiful-but-parochial English village for good measure. I’ve set up a knotty problem, and invited Poirot in to solve it. Those are the true verbs. So if you read articles claiming that I have accosted, ambushed, anointed, electrified, embalmed, exhumed, hijacked, kidnapped, ransacked, reified, sabotaged, sanctified, transplanted or trepanned Hercule Poirot…please be as sceptical as the detective himself. Not everybody tells the truth all the time.

HOW THE NAME CATCHPOOL WAS PICKED:

The Graveyard Directory

Some writers, I’m told, look for their characters’ surnames in telephone directories. I don’t – it seems too obvious. Or too deliberate: if you go looking for names, you’re bound to find them, of course, but I’ve always had a superstitious hunch that the names you find by accident are always going to be better and more satisfying somehow. (This is probably silly, I’ll admit, but no sillier than many of my other deep-rooted convictions, now that I come to think of it. I think I’ll stick with silliness.)

One day last year, shortly after agreeing to write a novel starring Hercule Poirot for Agatha Christie’s publishers, I found myself walking around a cemetery near my house. My husband and I wanted to go out for a walk after lunch, and he suggested the cemetery. I raised some sceptical eyebrows (roughly two, as I recall). ‘You’ll love it there,’ said my husband. ‘It’s really beautiful and atmospheric.’

He was right. No one has been buried at Mill Road Cemetery in Cambridge, England, for many years, and so the place has a shady, overgrown magic about it. As we walked around it, I started to notice some of the surnames on the graves, and how they were different from contemporary surnames. They had a classic, old-fashioned feel about them. The one that stood out in particular when I saw it carved into a gravestone was ‘Catchpool’. ‘Isn’t that an amazing name?’ I said to my husband. ‘I can just imagine a Catchpool, in a tweedy suit, with a handkerchief in his pocket, perhaps with his initials sewn on it…’ I stopped speaking and walking at the same time. This was it! I decided silently. This was where I was going to find names for the characters in my Poirot novel.

Catchpool had to be the most important character after Poirot, but I needed more names – lots of them. Instead of the phone book, I would use the graveyard as my directory. I walked around the cemetery day after day, and the strange thing was that, just when I thought I’d got them all, I would notice a stone I hadn’t spotted before, and add a new name to my list. In the end I used several in The Monogram Murders: Catchpool, Brignell, Negus, Sippell. One day I went to a park in St Albans that had a graveyard next to it. I thought, ‘I’d better just check this one too,’ and within seconds I had the surname Ducane, which I loved and added to my cast list in a prominent position. I made sure never to use the same Christian name from the gravestone with the surname – that would have felt like too much of a boundary violation.

In January this year, I decided to get a dog. I was spending so much time walking round the cemetery looking for names, and I’d noticed that lots of dogs are walked there. The dog-owners stand to one side and chat while the dogs play and romp together on the grass, between the stones. ‘I’d love to have a dog,’ I thought. A few weeks later, I had an eight-week-old Welsh Terrier called Brewster. He now comes with me to Mill Road Cemetery nearly every day, and meets his canine friends there, while I stare past their owners at distant headstones, in search of suitable names for future books…

Agatha’s influence on Sophie’s writing

When my agent first suggested to me that I ought to write a new Hercule Poirot novel for Agatha Christie’s publishers, I knew two things straight away: that this might be the most exciting creative challenge I could ever undertake, and that I would not want to write a continuation novel for any other writer, not even one that I loved. I’ve always been a huge fan of Iris Murdoch, for example, but to try to write a novel featuring one of her characters wouldn’t have worked for me at all. It would have been too contrived. I’d have felt like an actor playing one half of a pantomime horse, out of synch with the other half and in an ill-fitting costume.

The idea of writing a Poirot novel did not feel like that at all – which, if you think about it, is rather odd. Why didn’t it? Why did it feel so natural and possible? I think it’s because Agatha Christie’s influence is such an integral part of my writerly DNA, and always has been. She was my main influence, and the writer who made me fall in love with mysteries. I discovered her early – at twelve – and I’d read every word she’d published by the time I was fourteen. I was hooked. And a pattern had been firmly set up in my mind, the blueprint for what I believed an ideal detective story ought to be: an intriguing, structurally ambitious mystery – far more interesting and puzzling than simply ‘Here’s a corpse – who killed it?'; a super-clever detective who reliably and brilliantly solves every last puzzle at the end; an abundance of clues, indecipherable when we first encounter them, but making perfect sense once we’ve heard the detective’s explanation; the apparently impossible being shown to be possible; the combination of a fun, hooky read with psychological insight and an awareness of the depths of darkness in every human psyche.

When I set out to write crime fiction, I didn’t think to myself, ‘I’m going to model myself on Agatha Christie’ or ‘I am going to be a crime writer in the Christie tradition’. Nevertheless, the Queen of Crime’s example must have been strong in my mind, because I wrote mystery novel after mystery novel that opened with what I thought of as ‘an Agatha-ish beginning’. What I meant by this was: something so puzzling appears to be happening that readers cannot begin to speculate what might be going on, and fear that the only way the idea can be made to work is by resorting to the supernatural. So, in my novel The Dead Lie Down (which is called The Other Half Lives in England), a man confesses to the murder of a woman who isn’t dead. No matter how hard the police try to convince him that he can’t possibly have killed her because, look, there she is, alive and well and claiming never to have heard of him, this man continues to insist that she can’t possibly be still alive, because he killed her – yes, that very same woman – several years earlier. My novel Kind of Cruel starts with a woman arrested for murder because she uttered the words ‘Kind, Cruel, Kind of Cruel’ in a confidential hypnotherapy session and those same words were the only clue found at the scene of a brutal murder – but how could detectives have known that the heroine said these words to her therapist in a private therapy session overheard by nobody?

The trick is to show, slowly and logically, how what appears to be impossible is in fact eminently possible. Agatha Christie pulls it off brilliantly in Sleeping Murder, Murder on the Orient Express, And Then There Were None, Sparkling Cyanide and many other of her novels, and I try to do it in the crime fiction that I write. I didn’t realize until I was asked to write a new Hercule Poirot novel that, from my very first attempt at crime fiction when I was a teenager, I had been trying to write like Agatha Christie in so many ways. Being asked to do so openly and officially, and taking up that challenge, felt like a sort of literary coming out of the closet – a closet full of old paperback editions of Agatha Christie novels, the ones I collected as a teenager. After coming out of it, I wanted to crawl back in and reread all those wonderful books!