The Pale Horse Transcript

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A friendly warning: there are major spoilers for The Pale Horse by Agatha Christie in this episode.


Caroline: I think we’re all quite comfortable with the idea of real life events inspiring fiction — it’s not for nothing that some of the most critically acclaimed films that come out every year are the ones that have “based on a true story” at the beginning. Crime fiction is no exception to this. I’ve talked about this a fair bit on this podcast, discussing the ways in which some of the most famous murder cases in history, from Crippen to the Brides in the Bath and more, inspired authors working in the golden age of detective fiction in the 1920s and 30s.

That’s the expected order of events, isn’t it? A crime is committed, it becomes a public sensation with huge amounts of media coverage, and therefore shifts popular narratives around innocence and guilt. Writers respond to that, importing new tropes and ideas into their work, and readers recognise it.

But what if it happened the other way around? What if life imitated art? One particular book seems to have had a strong pull on people in this regard — not only as an inspiration for murder, but also equipping would-be sleuths with the knowledge to save victims before it was too late.

This is the story of The Pale Horse.


Welcome to Shedunnit. I’m Caroline Crampton.


Agatha Christie’s The Pale Horse was published in 1961, a long time after the so called golden age of detective fiction was over. Although she herself started her career at the beginning of the 1920s, forty years later many of her fellow detective authors from that prolific period of whodunnits between the two world wars had passed away or moved onto different kinds of writing. Christie had also broadened her range, to be fair, writing some romantic fiction as well as for the stage, but she never abandoned her original form. Indeed, by the time The Pale Horse came out she’d pretty much published a detective novel a year for three decades.

Of course, over time there had been some shifts and alterations in her style. Later Agatha Christie is generally characterised by more thriller-esque plot elements and less of a reliance on the true golden age rules. She had always enjoyed breaking up appearances for her regular sleuths Poirot and Marple with books that focused on one off characters, but these became darker and more preoccupied with contemporary themes. The Pale Horse is just such a book as this. The previous year Christie published The Adventure of the Christmas Pudding, a collection of short stories mostly featuring Poirot, and the year after she put out The Mirror Crack’d from Side to Side, a classic of the Miss Marple in St Mary Mead type. What came in between was utterly, completely different.

There’s something deeply disturbing about The Pale Horse. Perhaps we shouldn’t be that surprised — Christie took its title from the Book of Revelation in the Bible: the full line being “And I looked, and behold a pale horse: and his name that sat on him was Death, and Hell followed with him.”

Sarah Phelps: It was the fact that you had this sort of cheerful, sunlit existence, which in the book always seems to bounce through. And it’s almost got a kind of boy’s own adventure quality, the novel has. And that there are these fierce little seeds planted in the book, which just make me go, what’s that doing there? What is that detail doing there? It doesn’t seem to have anything to do with story. And yet to me, that is the story.

Caroline: This is Sarah Phelps, a screenwriter who has now worked on five television adaptations of Agatha Christie works. Her latest, of The Pale Horse, just aired on the BBC in the UK and will shortly be available internationally. It was the deep strangeness of the book that hooked her in from the start.

Sarah: As I was kind of reading, I kind of became really focused on for me the things that didn’t quite fit. And that’s the way I’ve read all of the Christie is that I’ve worked on for adaptation, which is I think that there is an internal kind of conflict. And in the future, who knows at somebody will do some incredible kind of like academic study on Christie and the conflict and tension between the book she wants to write and the book she knows people want to read. You know, popularity is a double-edged sword. People want to read a particular kind of book. They want to read a Christie. But I think that Christie wants to write about things that might not suit being popular. That might be a little bit more out there, a little bit more subversive, a little bit more sly. So she’s got to contain them in a kind of in a way that she sort of almost drops a clue. She drops a little close, something that doesn’t feel quite right in that sort of tone of the story. And and that’s what I follow.

Caroline: For example, she was really struck by the seemingly strange tastes of the novel’s central figure, Mark Easterbrook.

Sarah: There’s a detail in the end, the story about Mark Easterbrook, and that he lives in an area of the Kings Road, which is actually pretty squalid. He doesn’t need to live there. And people say to him, why do you live there? And he says, I like it. He likes the noise and he likes the kind of the the raucousness of it all. But even as he’s saying he likes it, he also has this little detail where he talks about the smell of girls, unwashed hair. And it’s sort of done with a kind of distaste, but also with a thrill. And I thought, well, there’s a character detail that I’m going to follow.

Caroline: This all helped Sarah to set the tone of her own adaptation, which certainly dials up the weird and unsettling aspects of the plot. But they’re there already — after all, the whole story revolves around a former village pub called The Pale Horse, which is now inhabited by three old women who seem to be witches. Mark finds out that they’re part of a very efficient “murder to order” conspiracy — pay your money, sign a contract and these three will perform a ceremony that soon sees your chosen victim die of apparently natural causes, leaving you completely free of suspicion. Christie’s description of the ceremony is a fascinating combination of the old and the new. A cockerel is slaughtered for its blood, but there’s also a very scientific box that scans an object owned by the victim in order to better direct the supposed “death rays” in their direction. As Mark says, it’s a ritual carefully designed to contain something for everyone, whether traditionalist or modern sceptic.

It is — and I’m afraid that this is where the spoilers come in, so beware — just a very clever piece of misdirection. What eventually tips Mark off to the true nature of the plot is the one thing all the victims of the Pale Horse seem to have in common: they lose hair before they die. This is a really profound piece of symbolism, Sarah says, and it goes to the heart of how she sees Christie’s work.

Sarah: Hair is important. And it’s sort of thrilling because her is both it’s sort of, you know, the woman’s crowning glory, the beautiful tresses, the silken mane, the all the rest of it. And yet it’s also disgusting. And you think about hair growing in the grave after death, hair falling out of your head and hair collecting in hair brushes. And you also think of the hair that was shaved off people in camps and it becomes rather horrible. And as well as being this glorious thing that’s about sex and life and everything else, it becomes a sort of harbinger of an apocalyptic sort of genocidal way of thinking about humanity. It’s it’s really, really unnerving. And also, you know, that by this point, people were understanding that radiation sickness made your hair fall out. So it was it was for me when I was reading The Pale Horse, I was just thinking, obviously, the Pale Horse is a puppet. It’s also the you know, the one of the one, you know, a harbinger of the apocalypse that all the time that she’s writing in these sunlit villages and these sort of charming little fates and these tea parties on vicarage lawns, that this is long, long shadow of of horror that falls across it, the horror of a technology that can obliterate him, a human being to her, to a shadow on the wall, and the horror of Western industrialized slaughter can do in, you know, in Europe. And I just kept feeling this shiver going through my blood and thinking, right then that’s what I’m going to write about.

Caroline: After the break: what the Pale Horse was really up to, and how it influenced a real life murderer.

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So what, other than witchcraft, can make people die from apparently natural causes, but also make their hair fall out?

Kathryn Harkup: Thallium is an element in the periodic table. It’s a metal. It’s rather uninteresting as an element, but it does slightly more interesting things when it’s made into a salt. If you swallow metals, they they don’t really dissolve in the body very well. So they’re not such good poisons. But if you turn metals into salts by combining them with another combat and other elements, then they become much more accessible to the body and they become much more toxic. And that’s the case with thallium.

Caroline: This is Dr Kathryn Harkup, a chemist and the author of A is for Arsenic: The Poisons of Agatha Christie. There’s a whole chapter in that book about thallium and The Pale Horse, and I highly recommend it if you’d like to understand this stuff in more detail than I can fit in one episode. Anyway, here’s what thallium will do to the unsuspecting poisoning victim:

Kathryn: The tricky thing with thallium is a whole host of things happen to people. From a chemical point of view it’s similar enough to potassium to fool the body. So the body needs potassium. It’s essential to our health. So if the body sees something that looks like potassium, it grabs hold of it and it tries to use it in the same way. The problem is that thallium is not potassium, so it does a rubbish job. So it will stop enzymes working in the correct way. It will mess with your nerves and all sorts of other things because it’s not doing what it should do. So then the body realizes that something is wrong and it tries to get rid of the thallium and it tends to get rid of it in saliva. So, of course, you swallow your saliva back down and the stomach reabsorbs it and you just continuously repoison yourself. So finding it is truly horrible and it’s doing all of these little subtle, malevolent little changes within the body that if you make too many of those changes and adjustments can be fatal.

Caroline: Because every body can respond differently to the presence of thallium, it can be really hard to diagnose that that’s what’s causing symptoms like hair loss, pain and nausea.

Kathryn: So historically, it has been very difficult to diagnose thallium poisoning because it produces so many different symptoms. Those at a famous real life case in the early 1970s, when one person had been poisoned with thallium, no, there was several people. And they had been seen by a combination of something like 43 medical experts and not one of them diagnosed thallium. So you can see how deceptive and particularly nasty this is as a poison.

Caroline: Even though Christie was very accurate in describing the effects of thallium in The Pale Horse, as a poison it’s rare enough to still give the reader a frisson of the supernatural. Unlike arsenic and cyanide, it’s not exactly a common one in detective fiction although there is a Ngaio Marsh novel, Final Curtain, that also uses it. But in the 1960s when the book was published, it was fairly easy to get hold of, as it was still included in creams for treating skin conditions like ringworm. And this is where fiction intersects with real life.

Kathryn: It’s astonishing that out of Christie has been cited in a murder trial.  Not many fiction writers have that dubious honour. But there was a case. A man called Graham Young had poisoned several of his colleagues at work and he had used thallium.  And this had occurred in 1971, 10 years after the publication of The Pale Horse. And if you read The Pale Horse and you read about the Graham Young case, there are so many similarities and parallels. It is another thing. So I’m not surprised that people ask the question, was Graham Young inspired by The Pale Horse? Now, to be honest, Graham Young had such an unhealthy obsession with poisons and poisoning people. And he did his own research. He was frighteningly well read in this area that there was nothing Agatha Christie could have taught him. He knew it already. He claimed he’d never read the book, but his sister said that it was the sort of book he might have read because of the subject matter. It would have interested him.

Caroline: Kathryn has actually written a much more detailed account of Young’s astonishing career as a poisoner, which I’ll link to in the show notes, but suffice it to say he was a very unpleasant man who started off by putting atropine in his sister’s drink when he was a teenager and ended up doctoring the tea run at the factory where he worked with thallium and poisoning eight people, two of whom died. And, like the culprit in The Pale Horse, it was his hubris and desire for the spotlight that gave him away in the end — he seized the floor at an employee meeting about the illness that was going around the workplace and talked in such detail about metal poisoning that he aroused suspicion that eventually resulted in his prosecution. He’d evaded capture for so long for precisely the same reason that the murderer in the book does too, because he carefully chose poisons that gave his victims natural-seeming symptoms so that the real cause of their illness wasn’t identified until it was too late. Thallium poisoning can be quite effectively treated with a compound called Prussian Blue, Kathryn says, which traps the thallium within its structure so it can be excreted safely, but it has a much higher chance of working if administered early on.

However, despite all the notoriety that Graham Young brought to Christie’s book, the legacy of The Pale Horse is not all grim.

Kathryn: This is the worrying thing about doing research into poisons. I mean, seriously, if the police ever come through my front door and look at my shelves, I’m in trouble. It’s a worrying collection of books that I have. And it must have been exactly the same for Agatha Christie.  And the risk of writing something like The Pale Horse. Are you going to inspire someone to mimic these actions? Well, I would hope not. And actually to counterbalance that The Pale Horse, because of its accuracy, because of its attention to detail. People have recognised thallium poisoning in others and been able to save lives. So knowledge is never in itself, good or bad. It’s what you do with that knowledge.  So having accurate descriptions of poisoning can be of enormous benefit in one circumstance. But good, very, very, very slim risk that people like Graham Young stumble across it.

Caroline: So there you have it: a spooky story with a solid scientific basis that may well have inspired a real serial poisoner. As someone who reads detective fiction for fun, the idea that there might be someone out there reading not for entertainment, but for practical tips, is darker than anything Agatha Christie ever dreamed up herself.


This episode of Shedunnit was written, narrated, and produced by me, Caroline Crampton. Many thanks to my guests, Kathryn Harkup and Sarah Phelps. You can find more information about their work as well as links to all the books and sources we mentioned at There, you can also read a full transcript.

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I’ll be back on 4 March with another episode.

Next time on Shedunnit: All At Sea.

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