Knock Knock Transcript

Caroline: Even the best detectives get stuck during their cases. The alibis are overlapping, the witnesses are contradicting themselves, and the medical evidence isn’t making anything clearer. As readers of whodunnits, as confused as our sleuths, it’s hard not to think about how much easier everything would be if the victim could just tell us what happened. If the dead could speak to the living.
At the same time as detective fiction was booming in popularity in the early twentieth century, so were ideas that death was not the end. Spiritualism, a term which encompasses a set of beliefs and techniques that are to do with making contact with those who have “passed on” beyond this mortal plane, was also rapidly attracting fans in the 1880s and 90s and the advent of the First World War only increased the number of grieving relations looking for solace in this way.
Although the traditional “rules” of golden age detective fiction prohibit the inclusion of supernatural plot devices, many authors including Agatha Christie, Dorothy L. Sayers, Gladys Mitchell and more made use of seances, mediums and spirits in their work. On the surface, applying logical deduction and listening to the whisperings of wayward spirits seem to be two completely different things, but they are intertwined in the detective fiction of this period in some fascinating ways. Perhaps the detective and the medium have more in common than the likes of Hercule Poirot would like to admit.

Today, we’re going to let the dead speak.


Welcome to Shedunnit. I’m Caroline Crampton. Today, we’re going to learn more about the rapid growth in the popularity of spiritualism in Britain in the 1880s and 90s, the way the First World War turbo charged the public’s demand for seances, and the impact that all of this had on golden age detective fiction.


First, let’s be clear what it is that we mean by spiritualism. The word itself, when used to mean the belief that the spirits of the dead can hold communication with the living, especially via a medium, only surfaced in the mid nineteenth century. It can all be traced back to a pair of American sisters, Maggie and Kate Fox, who in the late 1840s convinced first their parents, and then their neighbours, that their house was haunted by an invisible spirit. They could communicate with it via rapping noises, with it counting out their ages or answering yes or no questions via a code they worked out. The word spread among family friends and the wider community that these girls could talk with the dead, leading to the first major public seance of this type in Rochester, New York on 14 November 1849. The Fox sisters quickly became a public sensation, and other mediums began to hold their own events as the popularity of spiritualism spread. Even at the beginning, there was a strong strand of entertainment to it in both Britain and America. People enjoyed getting mediums to predict what would happen to their investments or their love affairs, as well as the more serious matter of trying to contact dead loved ones, and public seances seem to have often had a music hall like atmosphere, although private ones might be more sombre.
Spiritualism seems to have appealed to people across the boundaries of class and profession. It’s by no means the case, as is sometimes assumed, that only people who had less access to education were attracted to a belief system like this; eminent scientists, writers and politicians from the late nineteenth century were just as keen on it, and in many cases saw it as a way of reconciling the sometimes conflicting spheres of advancing science and religious faith. Perhaps the most famous of these well-known enthusiasts, and the most relevant for our purposes, was Arthur Conan Doyle — creator of Sherlock Holmes and a great influence on many writers of detective fiction’s golden age. He encountered spiritualism in the 1880s via a book written by an early American spiritualist, and was greatly intrigued by this account of a man able to communicate with his wife after her death. He even had a chance to participate in a few seances at the home of a patient while practising as a doctor in Southsea, and in his memoirs wrote that “I was so impressed that I wrote an account of it to Light, the psychic weekly paper, and so in the year I actually put myself on the public record as a student of these matters.”
Conan Doyle was an early member of the British Society for Psychical Research, a group founded in the early 1890s to investigate spiritualism and other ghostly phenomena with a scientific approach. It might sound absurd to us now that a man with a medical degree, who famously created a detective who believed in the application of logic and rational deduction above all else, could fall so heavily for a belief system that relied so heavily on the supernatural, but for Conan Doyle and his fellow late Victorians, it seems there was no inherent contradiction involved. The late nineteenth century was a moment of huge curiosity and a sense that all unknowns could be conquered if a sufficiently open mind was applied. So many of the technological and medical advances at this time would have seemed like magic. Imagine using a telephone for the first time, and hearing the voice of someone hundreds of miles away from you. In that context, is it such a stretch to believe that the spirit of someone who had died could be trying to get in touch with you?
The First World War was devastating for Conan Doyle, as it was for millions of others around the world. Too old for active service himself (he was over 55 in 1914), he lost at least ten members of his immediate family to the war, including his eldest son Kingsley. By this time he was at least two decades into his explorations of spiritualism, so it followed that he tried to use seances to contact his departed loved ones and receive some comfort from the fact that they had peacefully passed on. Conan Doyle was by no means alone in this — in 1914, there were 145 societies affiliated to the Spiritualists National Union in Britain; by 1919, there were 309, and by 1932, over 500, as well as an estimated 100,000 home seance circles in operation. The open support of spiritualism by celebrities like Conan Doyle and the famous physicist Oliver Lodge was part of its popularity — these men were the psychic influencers of their day. We might primarily know Conan Doyle as the creator of Sherlock Holmes, but nearly a third of the books he published in his lifetime were about spiritualism or paranormal activity, and later in life that’s what his reputation was largely built upon. So much so that when Agatha Christie infamously disappeared in December 1926 (check out episode 4 of this podcast for more on that), Conan Doyle was allowed by the police to take one of her gloves to a spiritualist medium called Horace Leaf to see if he could divine her whereabouts. Conan Doyle and his second wife were even said to have rehearsed their codes and signals so that they could still communicate if one of them passed away suddenly before the other.
It’s not hard at all to understand why the war caused increased interest in spiritualism. Church attendance was in decline, and for many the idea of cutting out the middleman so to speak and communing with the dead directly was very attractive. In a situation where the sheer volume of carnage was frequently too great for any kind of administration, families were often left with no closure or answers as to what had happened. “Missing presumed dead” was a common designation when no body could be found. But if a seance could reach a spirit, happily ensconced in the afterlife, the lack of physical remains might hurt just a little less.
All of which is to say, the tenets and tropes of spiritualism were very widely known and understood in the time that the great detective novelists of the 1920s and 30s were working. In its purest and most sincere form, spiritualism has a lot in common with the aims of your average sleuth, seeking as it does to give a voice to the dead and vindicate their narrative. But inevitably for such a popular belief system and activity, spiritualism became a vehicle via which charlatans and fraudsters on the take could exploit the vulnerable, and as such is a very useful plot device when it comes to crime. Plus, even if the rules don’t technically allow it, the addition of a spooky frisson can do wonders for a whodunnit.

After the break: how a harmless bit of table turning can lead to murder.

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Before we get into some details of how spiritualism was used in detective fiction more generally, let’s go over some basics for the uninitiated among us. A seance, meaning literally ‘a sitting’, is when a group of people gather together with the intention of contacting spirits. A medium is someone with particular sensitivity to this phenomena, who can contact a so-called “spirit guide” and ask them to in turn connect with the particular dead individuals those in the room with to converse with. I haven’t been able to find any precise gender breakdown, but in fiction at least, mediums are more often women than men, no doubt because of ideas about feminine intuition and sensibility. To have the highest chance of successful contact with the spirits, it was advisable to sit in a darkened, cold room with all the sitters gathered in a circle around a table, holding hands and focusing their minds on the goal. The arrival of said spirits might be accompanied by a dimming of the lights, or a slight haze in the room, but most often they made themselves known by rocking the table (hence the nickname for a seance, table turning) or loud knocking noises. These last were the usual way in which spirits communicated — the medium would ask yes or no questions, and the spirit could knock out the answer, one for yes and two for no. In some cases, the more longwinded alphabet technique was used, where one rap signifies a, two b, and so on. This is how names would be spelt out, so that the sitters could be sure that it was their own loved one who was now present in spirit form.

Of course, an awful lot of these conventions were developed with manipulation in mind. Professional mediums and their accomplices had ways of making sure every sitting produced some memorable effects, in order to ensure that they were asked back. Even the Fox sisters, whose ghostly rappings had begun the whole spiritualist movement, eventually admitted late in life that it had all been done by cracking their joints, especially in the feet — an art which required much practice and muscle strengthening exercises to do consistently. The confession was recanted again a year later, but the damage had been done. Once the suggestion of fraud hung around the Foxes, their audiences dwindled as people turned to other quote real mediums.

Perhaps the best recap of the techniques mediums might use to produce an exciting seance can be found in Dorothy L. Sayers’ novel Strong Poison from 1930. I’ve mentioned this book a few different times in Shedunnit episodes — it’s a particular favourite of mine and has plenty of different themes — but for our purposes today, let’s focus on the character of Miss Climpson, who is a middle aged woman employed by principle sleuth Lord Peter Wimsey to undertake inquiries that are too quote delicate for a man to involve himself in. In the scenes we’re interested in today, Miss Climpson is on a mission to discover a concealed will in the house of an incapacitated elderly invalid, and if she can’t do it quickly then an innocent person will hang for murder. She therefore, with many prickings of her extremely over active conscience, resorts to underhand measures. The invalid’s nurse, she quickly ascertains, is very interested in spiritualism, so Miss Climpson reinvents herself as a medium and conducts a successful seance in order to gain the nurse’s trust. To do this, she gets hold of a small metal soapbox and fixes it to an elastic garter, and we are told that: “When clasped about Miss Climpson’s bony knee and squeezed sharply against the other knee, the box emitted a series of cracks so satisfying as to convince the most sceptical”. In addition, she hides a homemade wire hook up each long, wide sleeve of her black velvet rest gown, so that she can catch it onto the edge of the table. This means she can rock and turn it without removing her hands from their clasp with her fellow sitter — an important element if she is to be believed.

A seance like this, where the reader is in on the plot from the start, is a popular trope among detective novelists. A sleuth can use a belief in spiritualism among their suspects or witnesses to break through stubbornness or a resolve to conceal vital clues — people who even half believe that a spirit might manifest are vulnerable to suggestion. Agatha Christie memorably has Hercule Poirot do this at the denouement of 1932’s Peril at End House. It’s one of my favourite endings of hers (and don’t worry, I’m not going to spoil it here), mostly because the oh-so-rational detective momentarily abandons the order and method of his little grey cells and instead indulges in a bit of parlour theatre in order to prove his culprit’s guilt once and for all. The faithful sidekick, Captain Hastings, is suddenly declared by Poirot to have “pronounced mediumistic powers” (a surprise to Hastings himself, who is such a steady, conventional character) and a seance is quickly put in train before anybody can object. Of course, the reader knows it’s all a fake, but the way Christie writes about it makes it clear that the characters (other than Poirot and Hastings) believe it to be real, or at least that it is possible that it could be real. That’s why it’s such a powerful tactic, and it’s testament to the huge and widespread popularity of spiritualism in the 1920s and 30s that it would be so. Even if they weren’t an active believer, everyone would know how to hold a seance. There’s an homage to this scene, by the way, in Murder Most Unladylike by Robin Stevens, who was a guest on the Back To School episode of the podcast — her schoolgirl sleuths, who are at boarding school in the 1930s, use a staged seance as a way of progressing their case too, although they use a ouija board rather than relying on knocks to spell out letters, the board being left over from when they were a spiritualist society rather than a detective one. As well as being part of a grand tradition of seances in detective fiction, this is a very recognisable scene to all the former teenage girls out there, who scared themselves silly with this stuff when they were at school.

Authors used the tropes of spiritualism in their fiction is as a way of including elements of the supernatural without actually abandoning the puzzle-based format of the classic whodunnit. There’s a very dramatic and engaging example of this in John Dickson Carr’s The Plague Court Murders from 1934, in which a family estate is supposedly haunted by the original owner, a hangman. A seance is to be held in the house to commune with this malevolent spirit, and a psychic and his medium are invited to run the show. Yet the psychic is found stabbed to death with a dagger owned by the deceased hangman, the body found in a small stone cottage with all doors and windows locked. The ground around the cottage is completely undisturbed, and all possible suspects were actually conducting the seance at the time of death, meaning that they were all holding hands. This is the first appearance of Dickson Carr’s detective, the barrister Sir Henry Merrivale, and he has to untangle all of this confusion. The story is venerated as a classic of the locked room genre, a so-called “impossible crime”. Here, the sleuth must find a practical explanation for the murder rather than resort to the “it was a ghost” solution, banned by the traditional rules of detective fiction. The seance, of course, functions both as a way of introducing the ghostly atmosphere but also as a more mundane plot device, keeping all the suspects together and supposedly giving them an alibi. There’s something similar in Gladys Mitchell’s When Last I Died from 1941 as well, with central sleuth Mrs Bradley renting a house by the seaside that has a ghostly past, ostensibly because she wants to hold some seances. A diary is discovered in the house (and printed as part of the book) which seems to describe the events leading up to the murder of psychical researcher Tom Turney, written by his cousin Bella Foxley, great niece of the house’s previous owner. As in Dickson Carr’s story, Mrs Bradley must sift through all the evidence and speak to all the witnesses she can find in order to sort out the supernatural from the mundane, and thus find the real truth of the case. In this novel, Mitchell is very clearly influenced by MR James, the hugely popular and influential author of classic ghost stories who had died in 1936. The spooky atmosphere of the house and the story Mrs Bradley uncovers is extremely well drawn, with the added bonus of a murder case on top.

It’s Agatha Christie, though, who found two of the most unusual uses of spiritualism and seances in detective fiction. The first comes in The Sittaford Mystery from 1931, in which a party of neighbours gathering in a remote Dartmoor village one evening in the depths of winter decide to try their hand at “table turning” for amusement. It’s all fun and games for a while, but then a genuine spirit seems to show up and declares that an absent friend from the area, Captain Trevelyan, has been murdered. As this all happens right at the start, it’s no spoiler to say that when one of the sitters heads off through the snow to check on his friend, he finds him dead. Once again the detectives have to work out if there is indeed supernatural agency at work, or whether the seance was very cleverly manipulated in such a way as to frighten someone, or establish an alibi, or for some other purpose that cannot be easily divined. The idea of spiritual interference clouds the view of the witnesses too, making the job of detection that much harder. Christie resolves it all in a way that I’ll let you find out when you read it, but she weaves the ghostly possibility very cleverly through the story, inviting the reader to dismiss the seance as a red herring while also tantalisingly suggesting that it holds the key to the whole mystery. There’s a great callback to Conan Doyle in this book too, since it shares a location and an atmosphere with his 1901 Sherlock Holmes story The Hound of the Baskervilles, and thereby also obliquely references his passion for spiritualism. Also, as a sidenote, this book contains my favourite type of Christie character — the highly competent one off female amateur sleuth. Here, that role is filled by Emily Trefusis, see also Lucy Eyelsbarrow. Perhaps I’ll do an episode about them at some point.

My favourite Christie seance, though, is in 1937’s Dumb Witness. Wealthy spinster Emily Arundell takes part in a seance on the day of her death, held by a pair of sisters from her village, the vegetarian (and therefore very eccentric) Miss Tripps. Emily isn’t a fully signed up believer in spiritualism, but her companions claim to have seen a mysterious luminous haze gathering around her as they sat together, which after her subsequent death from apparently natural causes, they interpret to be a foreshadowing of what was to come. Poirot, of course, takes nothing at face value, and once he is called in by a posthumous letter from Emily, he sets about examining everything in the harsh light of day. I won’t say any more, except that this is another brilliant example of Christie playing with the reader’s preconceptions about spiritualism — is it real, or was it faked somehow? Does it even matter to the case? You’ll have to read the book to find out.

Christie was no spiritualist herself, but she and other novelists of the time had great fun playing on the reading public’s knowledge and appreciation for the movement’s techniques and beliefs. As I’ve tried to outline here, there are so many different ways of incorporating a seance into a murder plot — hopefully when you encounter them in your reading now you’ll have an idea what to look out for.

That said, Christie did once step away from the supernatural ban imposed by the rules of golden age detective fiction. Her 1933 short story collection The Hound of Death is full of twisty little tales that focus on unexplained and ghostly phenomena. And there’s one in there titled ‘The Last Seance’, in which a medium reluctantly agrees to sit for a desperate grieving client one final time, with tragic results. After all of the times when she has baffled you and blindsided you with knockings and rappings, the sheer weird spookiness of this story really hits home.

What if, it seems to say, the dead could speak to us after all?


This episode of Shedunnit was written, narrated, and produced by me, Caroline Crampton. You can find more information about all the books and sources I’ve mentioned at the show notes for this episode at There, you can also read a full transcript.
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I’ll be back on 2 October with another episode.
Next time on Shedunnit: Off The Rails

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