by Alex Pavesi
She shook her head. ‘No one would do this to themselves. I’ve seen this kind of mesh used for cheap camping equipment. You can sit or lie on it and it will take your weight, but try to stand on it and with the pressure you’ll fall straight through. The lid must have been open, disguised as part of the wall. So when he stood on the bed he would have stood on the mesh.’ She tore the rest of the netting away from the edges. ‘The base is covered in spikes, barbed so that he became hooked on them. And this lever would have released that catch once he put his weight on it, which made the lid spring shut. Then he bled to death in the dark.’ A half-inch of blood filled the base of the hollow bed.
‘And the mosquito?’
‘Just a trick to get him to stand on the bed.’
Charles slammed his hand against the wall. ‘Such diabolical trickery. Maybe Unwin wasn’t one of the guests, then. Has it occurred to you that he could have come here weeks ago and set these traps in place? He didn’t need to be here to watch them play out.’
‘That doesn’t quite work. The traps wouldn’t be enough by themselves. Think of the man garrotted outside, for example.’
‘But all ten of them are dead?’
She put her hand to her forehead. ‘I know, but one of them must be guilty. It’s just a case of working out which one.’
‘Well, if we’ve reached an impasse, then I say that at this point we let the police take over. The tide still looks high enough.’
She rolled her eyes. ‘No, Charles. Come with me.’
They went back downstairs, to the lounge covered in ash and fragments of wood. ‘The chronology is fairly easy to establish. But let’s be explicit about it and the rest should fall into place. The first day is for arrivals. Then there are all the accusations over dinner and the first death, the woman who swallowed her fork. I imagine they retire early, too shaken to spend an evening talking to strangers. And the servants presumably too busy cleaning up the body to clear away after dinner. That could be taken care of at dawn. Meanwhile, two of the guests are poisoning themselves with candles. The other five guests wake up the next morning and make their way down here. But the servants have been dispensed with already and breakfast is not forthcoming. Perhaps they assume that both of the Stubbses have gone to the mainland, but eventually suspicion sets in. Two of the guests are sleeping implausibly late. They search the rooms and find the bodies and it’s clear that something sinister is underway. I would suggest that at this point they search the island for any intruders and find the bodies of Stubbs and his wife. That’s when things must have broken down; there had been five murders and there are five left alive. They find nobody else as they search the island, so they know that one of the five of them must be up to something. There’s an urgent conference in the lounge, complete with exploding logs. Rather than trying to find safety in numbers, they gather supplies and lock themselves in their rooms. There’s even a fight for the best room. Do you follow me so far?’
Charles nodded eagerly.
Sarah continued: ‘That may have taken them through to the second evening or the following morning, but at some point the two ladies leave their rooms and move their stash of supplies to the study next door. Why? Because the bedrooms aren’t safe. One man is boiled in the bathtub, another is slowly bleeding to death inside his bed. Between the two of them their screams would fill the whole top floor of the house. And both of them are behind locked doors. The older man, the one on the grass outside, is the only other guest left alive at this point. The two ladies knew each other before they came here so their suspicion lands on him. Whether justified or not, they run to the study and push the desk against the door.’
‘But then how did they die?’
‘Oh, that’s easy.’ She walked to the mantel and pushed in a loose brick. ‘When this is pulled out it creates a gap at the back of the chimney and smoke will pour into the room next door, through a hole in the wall. The door to that room has no lock, but locks whenever the window is open. You opened the window and I saw the bolt slide out from the doorframe; I could hear the pulleys running through the walls.’
‘And the window was too small to climb through. So they are being asphyxiated and the only way they can save themselves is by closing the window, the one thing they will never try? Unwin has a putrid sense of humour. So the older man outside presumably lit the fire that killed them? But you don’t think he is Unwin?’
‘Let me consider that for a moment.’
She sat down in one of the plush armchairs and began that habit again of applying pressure to her forehead to induce concentration, this time with the base of her palm. It didn’t matter now that Charles could see her doing it; he wouldn’t interrupt. He just watched, open-mouthed. He couldn’t hear her breathing and began to grow concerned, then she lurched upright as if waking from a nightmare. Her speech, however, was entirely calm.
‘No, he wasn’t Unwin. Though it’s true that his death is the hardest to explain. All along there has been another presence here, though I couldn’t quite connect it with anything. The schoolteacher, Mrs Richards, choked on a tine of her fork. Or so I told you, but I looked in her mouth and felt along her throat and there was no obstruction. Either I was wrong or somebody removed it later. We found two burnt candles next to two dead bodies, but we didn’t find any matches. The body in the bed was covered by a lid, itself covered with sheets to look like a bed. The lid was set to spring into place at a great deal of speed, and yet when we found it the sheets on top of it were perfectly neat. And that was inside a locked room, but we found no trace of the key. Then the two women that died in the smoke-filled room were locked in by the mechanism of the window being opened, but when we found it the window was closed. And the desk was neatly placed against the wall.’
‘Well, the last man left could have done these things. The man lying in the grass outside. And if he was Unwin he’d have had a key to all the rooms.’
‘Yes, but his death looks too much like murder. It was the hardest to work out, because there is so little of the mechanism left. But Unwin wouldn’t have attacked him outright, even with a garrotte: too much could go wrong. There had to be a trick to it. And of course it’s obvious when you step back and think about it. We found his body by the place where the boats are usually tied up: he had no reason to be there, unless he was about to take one. And how do you induce a man about to take a trip by boat to put a wire around his own neck?’
Charles had no answer for her.
‘By handing him a life jacket. Or something made up to look like one, with a wire in the lining. All it would take is some cardboard and cheap fabric. It goes over the head, then the wire is around the man’s neck and the weight is released. And that brings us to the other thing puzzling me: why none of them tried to take a boat on the second day, when half of their company was found to be dead. The sea was stormy then; they wouldn’t have made it. But I would have expected one of them to have tried it anyway; it’s a more palatable death than any of these. Unless there was someone there to talk them out of it, to persuade them to wait another day, someone whose authority on the matter had recently been shown to them.’
‘You mean?’
‘Stubbs.’
He gasped.
‘It was clear all along, I won’t forgive myself for missing it. He was the only one that knew the route here through the rocks. When the storms were raging on the second day he convinced them all to stay on the island. He had their trust because his wife had died; they thought of him as one of the victims. The deaths in the bed and the bath must have happened either that night or early the next morning, then the two women were killed by the morning fire. At high tide Stubbs announces it’s safe to leave and they find there are only two of them left. The trick with the life jacket takes care of that, then Stubbs cuts the boat loose and goes to join his wife. He has a full set of keys so he can tidy the place up first. It should have been obvious; his death is the only one that looks remotely like suicide.’
‘But I don’t understand. W
hat was his motive?’
‘I think he was dying. There was coughing, at night. And we found a handkerchief in his pocket, spotted with blood. What if he decided to take some others with him? People guilty of unpunished crimes. Only a servant would know so many secrets. And he was a devout man; remember the bible we found in his bedroom. Whether he saw his mission as justice or revenge, I don’t know.’
Charles was almost too shocked to speak. ‘My god, the man was a devil. I can’t comprehend it.’
Sarah gave him a look of sympathy.
He paused and took her hand. ‘Sarah, I am very proud of you. You really do have a mind for this kind of thing.’ She nodded, shyly. ‘But let’s not be too forthcoming with the police. We wouldn’t want to give them the impression that we’ve been snooping around here. I’m sure they’ll work it all out for themselves.’
The sun had just set when the two of them got into their boat; the tide was coming in again, after a long and tedious afternoon, and the worst of the rocks were covered.
Sarah spoke. ‘Charles, it has just occurred to me: should we attach a note to the front door, saying that we’ve gone for the police? In case anyone else comes here before we get back?’
He grunted. ‘It’s a noble idea, but I don’t have a pen, or any paper. It’s not very likely that anyone would come here at this time.’
‘But in the morning they might. And we don’t know when we’ll be back. There was a desk in the library, next to the kitchen. The top drawer had both a pen and some paper, I checked in there earlier.’
‘Well, then. You wait here and try to keep warm.’ He stood up; the boat rocked. ‘I shall be back soon.’
He strolled up the slight incline and through the front door of the house.
The window of the library looked out onto the short wooden landing where Sarah sat in the boat. It was dark inside; the generator had switched itself off long ago. But she saw the rough shape of Charles enter the room, saw the dark smudge as he walked past the window, then she heard him swear as he tugged at the stuck drawer, heard the metallic thump and the yelp of a hinge as the trap she’d seen there earlier clicked into place, heard the brief cry as his head was severed from his body. It was a quick death.
‘Charles,’ she said, ‘I told you it wouldn’t work.’ She took up the oars. ‘Forgive me, Henrietta.’ And she glanced in the direction of their house, wondering if the girl was still watching through the telescope. It was almost certainly too dark to see anything.
As she navigated through the rocks, along the route she’d memorized that morning, she found herself at several points rowing directly away from the meagre beach with its two dead bodies. And with the play of moonlight on the water, there were a few moments when it seemed as if Stubbs was winking at her.
10. The Fifth Conversation
Julia Hart finished reading the fifth story. ‘And with the play of moonlight on the water, there were a few moments when it seemed as if Stubbs was winking at her.’ She lowered the manuscript.
The rain was gone and the sky was a flat, moderate blue, with a few clouds of different shapes and sizes, like a range of hats in a shop window. Grant and Julia were sitting in a quiet churchyard at the top of a slight hill, about a mile along the coast from his cottage; they’d walked up there after lunch. The ground was already dry.
‘That was a bleak story,’ said Julia.
‘Yes, it was.’ Grant lifted his hat and wiped his forehead with a handkerchief. ‘Ten dead bodies discovered on an island. It’s an homage to my favourite crime novel.’
‘I thought as much.’
‘That ending was particularly nasty, when Sarah killed Charles for no reason.’
‘I suppose it wasn’t entirely unjustified,’ said Julia, ‘given the context.’
Grant shook his head in disagreement. ‘It’s another depiction of the detective as a malevolent figure, an arrogant character who sees themselves as superior to the law.’
‘And it’s another one set by the sea.’ Julia took out her notebook. ‘Is the sea an obsession of yours?’
‘No, I wouldn’t say that. It reminds me of my childhood, that’s all.’
Julia spoke hesitantly, remembering his outburst the previous night. ‘Did you grow up by the sea, then?’
Grant looked momentarily lost, watching her pen move back and forth. ‘We had holidays there, that’s all.’ She waited for him to say more, but he didn’t.
‘I think that one’s my favourite,’ she said. ‘In spite of how bleak it is.’
He pulled his hat down over his eyes. ‘I am glad to hear that.’
Julia was watching a pile of rocks, a few yards away from them. She thought she’d seen a snake slithering among them a few minutes earlier. Just a small one. But it could have been a trick of the light.
Grant got to his feet and pushed the hat back up to his hairline. ‘Let’s do some mathematics. I think it’s time I went through the actual definition, don’t you? It’s simple, really.’
Julia looked up. ‘I would like to hear it.’
‘Good.’ Grant found a broken olive branch, lying in the dirt by the rocks. He sat back down and started to draw in the sandy ground between them. ‘This is straight from my research paper, The Permutations of Detective Fiction. Section one, subsection one.’
He drew four circles on the dusty earth, and labelled them S, V, D and K.
‘Do you know what this is?’ he asked.
She squinted at the shapes, unsure of how to interpret his question.
‘It’s called a Venn diagram,’ he went on. ‘This is one in its embryonic form. Each circle represents a set, or a collection of objects.’ He drew a large oval around the four smaller circles, covering all of them, and scratched a C in the corner nearest her. ‘The sets are all made up of members of the cast. The cast is just the collective name we give to the characters in the book. Even the incidental ones. So the sets are collections of characters.’
‘Go on,’ she said.
‘The circles represent the four ingredients that we’ve already discussed: a set of characters called the suspects, another called the victims, the detectives and then the killers. To this we add four requirements. The number of suspects must be two or more, otherwise there is no mystery, and the number of killers and victims must be at least one each, otherwise there is no murder. We express those mathematically by talking about the cardinality, or size, of the sets: the cardinality of S is at least two, and the cardinalities of K and V are both at least one.’
‘Yes,’ she said. ‘That’s straightforward.’
‘Then the final requirement is the most important: the killers must be drawn from the set of suspects. K must be a subset of S.’
To illustrate this last point he rubbed out the circle labelled K and drew it again, smaller, inside the circle labelled S. ‘That is how we show subsets in a Venn diagram.’
‘And so far that’s just a summary of what we’ve said yesterday and this morning, I think?’
‘Correct. But it’s been stated formally now. And that defines a simple mathematical structure that we’re going to call a murder. The next line is very important. I put a lot of thought into the phrasing of it.’
She waited, her pen ready to write it down. ‘Go ahead.’
‘We say that a story qualifies as a murder mystery if the reader can sort its characters into these four sets, and – crucially – the set of killers is identified in the text after the other three sets have been completed. That sentence is what joins the world of mathematics to the imprecise world of literature.’
‘And that’s the entirety of the definition?’
‘Yes, that is all of it. Any further stipulations you might want to make – rules on when the suspects must be introduced, when the murder must take place, and so on – would just open you up to a number of exceptions and counterexamples.’
She looked puzzled. ‘I suppose its simplicity is what makes it hard to understand. It’s not the structure itself that c
onfuses me, but why it should be considered significant.’
He shrugged. ‘Mathematics often begins like that.’
‘There’s nothing about clues, for instance, which are a staple of the genre.’
‘Yes, precisely,’ Grant leaned forward, ‘that is exactly why it’s significant. With the definition in place, we can now make the argument that clues are not an essential part of a murder mystery. Go through any murder mystery and delete all the clues; you’ll still have a murder mystery. As long as it fits this structure. So the definition is liberating, to some extent. Do you understand?’
‘I think so.’
‘Let’s take another example, the case of supernatural crimes. They’re often considered forbidden in murder mysteries, but there’s no reason the murder shouldn’t be done by a ghost walking through walls as long as the ghost is introduced as one of the suspects before being exposed as the murderer. The definition tells us it will still be a valid murder mystery.’
‘Then what about the stories in this collection, The White Murders?’
‘Ah,’ he clapped his hands together. ‘That’s the other thing we can do with the definition, we can calculate with it. The standard murder mystery has a detective, a victim and some suspects, with no overlap between any of them, and a single killer taken from the group of suspects. Well, now we can look at what we might call the aberrant cases, where either the group sizes are irregular or two or more of the groups overlap. There are only four components to a murder mystery, so the number of permutations is relatively small. We can calculate and list every single one of them. Every possible structure. That’s what these stories were meant to explore.’
Julia turned to a specific page in her notes. ‘So we’ve had a murder mystery with two suspects, one where the victims and suspects overlap, another where the detectives and killers overlap, and one where the killers and suspects are the same?’
‘That’s right,’ said Grant. ‘And the defining feature of the story we’ve just read is that the victims and the suspects are the same. In other words, there are no suspects other than the victims and no victims other than the suspects. We know that one or more of the victims killed all the others. The diagram for that would look like this.’