Snow Job Too Small

"X marks the spot."

"Indiana Jones and the Last Crusade"

Guess it'll be starting to become warm again by the time this post goes online. I actually read this book during one of the hottest summers in Japan...

Six men and women nearing their thirties each make their way to the mountains near Otaru City in Hokkaidou to arrive at the Deep Snow House, the private residence of Tachihara Shigeru, retired teacher, photographer and self-proclaimed inventor. This group of six used to be in Shigeru's class in high school and have been invited to a small gathering at his home. Almost a year ago, they had a class-wide reunion, but Shigeru had an accident then, falling off the stairs at the restaurant they were eating/drinking at, which left him unable to walk. His former pupils received an invitation to visit him at his home and stay for a few days for skiing, but as they arrive, they do find it odd they are only six of them here, especially as some of them weren't even that close with Shigeru. When they arrive at the house, they are shocked to see Shigeru after the accident: he wears a mask, sits in a wheelchair and can't talk, having to use a computer-generated voice coming out of a robot to speak. As they talk things over, Shigeru explains he didn't send all these letters and that he never had any plans to have any parties at his home. While everyone wonders who then sent these letters, Shigeru says his former pupils might as well stay. However, strange events occur and when they look into some of Shigeru's private files, they find clues indicating a plot: for over a year now, a "pusher" has been active in Sapporo City, pushing people from stairs and elevations out on the streets, in malls and everywhere, injuring people severely. Notes on Shigeru's computer seem to suggest Shigeru suspect his fall wasn't an accident, but also engineered by the pusher, and that this pusher is one of his students, more precisely, one of the six students now present at his house. What is going to happen at this house, especially as a snow storm prevents anyone from leaving in Nikaidou Reito and Kuroda Kenji's Killer X (2001).

Killer X is the first novel in a trilogy, but also the second novel in a tetralogy. That might sound confusing... and it kinda is. So to explain: in 2000 publisher Kobunsha published the novel Hakuginsou no Satsujinki ("The Killer of the Silver House") by the author "Psycho Jun", an pseudonym to signify two collaborating authors. A quiz was set-up, and participants had to guess who these two writers were. 233 people made a guess, with only 8 getting it right. It was eventually revealed that the writers were Nikaidou Reito and Aikawa Akira. The next year, Killer X was published, this time a book written by a duo operating under the name "The Queen Brothers" (the name that Nikaidou and Aikawa were planning to use originally). It was later revealed this pen name belonged to Nikaidou Reito and Kuroda Kenji. Nikaidou Reito and Kuroda Kenji would pen two more novels in this series. So the first novel was by the duo of Nikaidou and Aikawa, and the remaining three novels by Nikaidou and Kuroda. The four books also all share the same theme of being closed circle mysteries set in ski resorts, so are often referred to as the Ski Mystery Tetralogy. So far so good. 

The confusing thing however is that there's also a binding factor only present in the three novels by Nikaidou Reito and Kuroda Kenji. Killer X is not only the title of the first book, it is also the name of an in-universe character. Killer X is a (fictional) mascotte figure created by a stationery maker and hugely popular. The titular Killer X is a former monk, and stationery and other merchandise featuring Killer X usually feature a visual of him, accompanied by English sentences with trivia about X, like  "X Is Monk" (sic) or "X Likes Cooking". Killer X as a character appears in three of the Nikaidou/Kuroda novels, thus these three books specifically are also referred to as the Killer X Trilogy. In Killer X, one of the characters is a huge of Killer X, and as it is the title, you can also guess the Killer X character is in fact connected to the mystery.

I have no idea how Nikaidou and Kuroda divided their work and planned out this novel, but I can say one thing: they were enthusiastic as hell. The book is not short, though very readable because of the simple prose, but it's crammed full with all things mystery readers like. The closed circle situation set-up of a house isolated from the outside world due to a snowstorm is of course very, very traditional, but there's plenty more of that to come, like a masked host who used a computer-generated voice to speak with his guests, who even denies he invited them, mysterious letters, a dark backstory of a person who randomly pushes people in the city, a mysterious companion to the host who seems to have secrets of her own, a group of high school comrades who aren't quite just friends anymore because of time passing but also because of personal history... There's a very detailed floor plan of the Deep Snow House too, which immediately gives the reader all kinds of ideas of how murders could occur there... The suspense parts of the book work well, and you can constantly feel something will go wrong, because somehow, not everything fits.

As a mystery novel, it's perhaps not exactly what you'd expect it to be. I at least had hoped for some bombastic locked room murder situation (and solution) from Nikaidou, which I didn't really get here. What I did get is a very complex, tangled web of narratives that is slowly unraveled. The story jumps between perspectives and times, showing us glimpses of one character in the present, but then for example jumping back to the perspective of the pusher while they are committing one of their crimes, only to jump to another character soon before arrival at the house etc. Keeping a keen eye for how everything is connected is not only necessary to solve the mystery, I'd say you also need to pay attention simply just to keep up with the plot due to all the jumping around. 

When the snow prevents anyone from leaving the house (note: nobody actually goes skiing in this book despite it being called the Ski Tetralogy!!), the mood becomes suspenseful, but also very slow, because little actually happens for a large part of the novel. It's mostly the ex-students trying to figure out who and why they have been gathered at the house of Shigeru, with a focus on the tripping accident of Shigeru some time earlier, when they were having a class reunion at a bar and Shigeru tripped down the stairs on his way back from the bathroom. So a lot of the actual criminal investigation is aimed at the past incident, while the present-day events are more about the building suspense of finding out what is happening in the first place, though slowly but surely, things are about to occur in the present-day too Ultimately, the mystery behind Shigeru's fall in the past is fairly simple, but also very adequately clewed (some of the clewing is even quite cheeky!) and I do love how it very naturally connects to the many other plotlines going on this book. Keeping all of the narratives in mind can be a challenge, but once this part of the mystery is solved, you can slowly see how a lot of the seperate narratives you have been reading come together. There's some great misdirection going too in regards to the motive, and I really liked how that was done, even if it sometimes borders on the unfair. The more memorable parts of Killer X is definitely how in the end all the disjointed fragments we saw are given their proper context,  though obviously, I can't really explain that without spoiling that/explaining too much in detail. The device of Killer X as a character was alright, though I am surprised they decided to use it as the title of the book too, as Killer X's role in the book isn't that important on its own. I am interested to see how Nikaidou and Kuroda will use Killer X in the following two books.

Oh, and there's one more thing to note: the very ending of this book does reference, and I suspect even spoils the previous book (Hakuginsou no Satsujinki by Psycho Jun = Nikaidou Reito and Aikawa Akira). I haven't read that one yet, but they discuss a certain character in a way that makes me think it's a fairly major spoiler? It might just be something revealed to the reader at the start of that book, but you might want to read them in order just to be safe.

Killer X was perhaps not the kind of mystery I had expected as a collaborative effort by both Nikaidou Reito and Kuroda Kenji, but I did enjoy the book overall. It is never revolutionary in the way it handles mystery tropes, but you can definitely feel both authors are confident in their art and used to playing with the familiar tropes of the genre to come up with something that is very recognizable as a mystery story, yet also bringing enough energy to also pack this "Definitely A Detective Story With All The Usual Twists" with a few good ideas of their own. This was a decent enough read, and it does make me interested in the other two novels, which I fortunately already have in my possession. 

Original Japanese title(s): 二階堂黎人、黒田研二『Killer X』 

The Secret of Terror Castle

The good king had died

And no one could decide

Who was rightful heir to the throne

"The Sword in the Stone" (Fred Darian) 

No cover art yet, so I'll just use the cover of the magazine with the first installment... 

As Luza wakes up, he still has vague memories of leaving home with his friends in search of the legendary Sea at the End of the World, but their trip soon ended in a disaster. The last thing he recalls is him facing certain death, which is Luza is so surprised to find him in the care of a young man called Romelia, who is very, very interested in Luza. For Luza is someone who shouldn't exist. It turns out an unconscious Luza was found by Romelia, who took him to his home in the Castle of Stone Spheres, where the last humans reside after a natural catastrophy wiped out civilization. While some of the previous society's knowledge still survives via books, technological advancements have been basically reset and the very small enclave of surviving humans now live in a walled village, which is collectively called the Castle of Stone Spheres, named after the enigmatic stone spheres that are scattered all around the castle. Romelia explains that for centuries, it has been believed that the Castle of Stone Spheres is all there is still to the world: the Castle of Stone Spheres is surrounded by total darkness and outside the castle walls is just ground that stretches into emptiness. All the food and other supplies the people consume has to be produced within the castle walls, which is why the community of the Castle of Stone Spheres is strictly regulated by the Nine Kings of the Night, who make sure the community is self-sustainable. Thirteen towers are embedded within the castle walls, each guarded by a priestess. All the towers contain a Crystal Skull, a mysterious device which can generate energy to light up the Castle of Stone Spheres. 

And that is why Luza is an impossibility: there's nothing outside the Castle of Stone Spheres, and yet Luza is not an inhabitant of the castle, meaning he is an outsider and came from beyond the castle walls. There has been no record of an outsider arriving in over two-hundred years of history. However, Luza is lucky Romelia found him, as Romelia does think there's something out there. His father, who studied the now extinct society, once ventured outside the castle walls to find what was waiting there, and while he died during his quest, Romelia still believes his father was right. Romelia decides to introduce Luza to one of the priestesses to see if they can help Luza get back, but they find her murdered inside her own tower, which they found locked from the inside. What's even more surprising is that the priestess had been decapitated! The Kings of the Night have the death of the priestess investigated, as each and every priestess is vital for keeping the castle running. Romelia however desperately tries to keep Luza's existence a secret to the Kings, as they are very swift to deal with anything that might endanger the equilibrium within the Castle. But Romelia and Luza soon realize it wasn't just one murder: one by one, the priestesses are killed in their own towers, each time found in a locked room. It's a race against the clock as Romelia and Luza try to apprehend the murderer and solve both the murders and the mystery behind the Clock of Stone Spheres in Kitayama Takekuni's 2026 novel "Sekikyuujou" Satsujin Jiken ("'The Stone Sphere Castle' Murder Case").

Wa-wait? Is this a brand-new entry in Kitayama Takekuni's Castle series? Why yes! Kitayama made his debut as a mystery writer in 2002 with  'Clock Jou' Satsujin Jiken ("The Clock Castle Murder Case"), which would be the first in a series of four novels, and with (at least) two novels that are somewhat related to this series (Alphabet-sou Jiken AKA The Case of Alphabet and Gettoukan Satsujin Jiken/The Moonlight Manor Murder Case). While the books in this series are standalone and not directly connected to each other story-wise, they all feature unique, fantasy-like worlds with some supernatural elements, with the main connecting tissue being that they all feature castles or grand manors as their main decor. There are some small references shared between the books, but nothing major. For example, a legend involving six decapitated knights and the name Geoffroy is featured in several books, though they do not per se refer to the exact same things. The major similarities between the stories are the castle settings, fantasy/science-fiction elements playing a role in the background, and perhaps the most important aspect: there is an emphasis on impossible murders (often featuring some grand mechanical trick behind them). In fact, Kitayama is known for his locked room murder situations with technical tricks because of this series and 'mechanical tricks' are basically what everyone associates him with. 

Anyway, Kitayama decided to return to his legendary series after two decades and so "Sekikyuujou" Satsujin Jiken was serialized across four installments in the magazine Mephisto between 2025-2026, with the actual book release scheduled for this June. And what a return it is! This is an immensely dense adventure, even by Kitayama standards. The reader is made aware fairly early on that there are thirteen priestesses in as many castle towers and that the murderer is killing and decapitating them one by one in locked rooms, so you start to think: "No way, he can't be serious...", but yes, the madman comes up with over a dozen of impossible crimes in this book! 

But more about that later. For first, I want to highlight the setting. The titular Castle of Stone Spheres is a very unique location, even within the series, as it's both a castle and a (walled) town: it's fairly open compared to previous castle because of that. But what still gives this book a claustrophobic atmosphere is the knowledge the Castle is all there is in the world; for some reason, the world within the castle walls is all that's been left after a catastrophe wiped out basically all of human civilization, and the community surviving in the castle has to be strictly administered to make sure it remains self-sustainable, as that's the only choice they have. Luza and the reader learn from Romelia however that there might be more to the history of the castle and the non-existing world outside, adding a grander, existential mystery on top of the more "mundane" locked room murders. There is also the mystery of the castle itself, which has existed for centuries and which for some reason, has stone spheres lying all around: the enigmatic stone balls vary in size and weight and can be found everywhere, from the town square to inside the priestesses' towers. They seem to be plazed haphazardly and nobody knows what their function is, and in fact, some even swear the spheres sometimes move about, as if they have their own will. These are all elements that tie in to the grand mystery Romelia tries to solve about the castle.

While Luza and Romelia try to save the priestesses, they find their quest hindered by the Nine Kings of the Night, who despise all those who threaten the balance within the Castle of Stone Spheres, which includes the free mind Romelia, and of course the outsider Luza. Romelia and Luza in particular find themselves targeted by Micthran, the King of Death, who seems to have an agenda of his own. He seems to know much more about the castle than anyone else, and it's this storyline that addresses the meta-mystery of the Castle of Stone Spheres. The climax of the clash between Romelia, Luza and Micthran is absolutely fantastic, with a shocking and insanely amusing truth awaiting the reader at the end. I'm not sure things work exactly as it's presented here, but the idea itself is just soooooo deliciously fun and yet simple to imagine, and I have to hand it to Kitayama, he actually had a looot of foreshadowing built into the story that points beautifully to this conclusion. It's this 'grand story' that will likely impress most readers of this book. 

Almost immediately after Luza's arrival in the castle, they realize there's a murderer on the loose who is after the priestesses and their heads, and for some reason the murderer is very, very focused on committing these crimes in locked-room situations. The victims are all discovered in their respective towers, but the exact situations are very different: in one, the impossibility comes from one of the big stone spheres being used to block the door from the inside (meaning the murderer couldn't have left the room after moving the sphere there), in another a priestess is found dead in a room even though Luza had been standing guard near the door, while another situation might involve an impossibility because the room itself couldn't be reached. With over a dozen of locked-room murders, it's no surprise the featured set-ups or solutions aren't all equally memorable or impressive, and while this is no short book, sometimes we do spend awfully little time at one crime scene before moving to the next already. That said, on the whole, Kitayama managed to come up a very entertaining novel and there are some really cool ideas going in some of the locked rooms. Some rooms for example may feature a rather simple trick when taken in isolation, but then Kitayama creates synergy with other locked rooms by cleverly transforming concepts used in one room and applying them to a different one. The use of one particular object in several locked rooms for example is quite memorable. Other locked rooms rely on very specific mechanical tricks that seem a bit gimmicky in a vacuum, though I do think it works narratively, because of something I will explain further below. The stone spheres also play a cool role in setting-up the locked rooms, like having a stone sphere blocking the door in one crime scene, or their presence being used to deny certain theories. The stone spheres are not always super present in the story, but when they pop up, they always make an impression because they end up either negating hypotheses or vice-versa, seem to be involved in the actual solution. The reason why the castle features so many of them in the first place is also addressed at some point, and it's a really clever idea too.

But what Kitayama really does well is taking the whole series of locked-room murders as... well, a series. The locked rooms are not discrete cases, but Kitayama develops them as a sequence, with the complete case taking on a surprising form when viewed in its totality. The way Kitayama does this and ties this analysis to the murderer is both original and a bit insane, in the good sense of the word. Some really clever clewing regarding the identity of the murder is conceiled within the execution of each locked room, giving functional meaning to the fact Kitayama used so many locked rooms in the story, beyond just the notion that having so many of them is fun. The Ellery Queen-like build-up of gathering the clues to identify the murderer is done in a very devious manner in this novel, and Kitayama is sure to use the unusual setting of the Castle of Stone Spheres in its fullest. Kitayama also goes absolutely nuts with diagrams in this book! Basically all the crime scenes are accompanied by a small diagram of the crime scene, so you already have seen plenty of them by the time you arrive at the the final chapter. And there the reader is treated to an absolutely epic summation of all the locked room murders that went on in this book, which of course is accompanied by again more than a dozen of diagrams! I honestly can't remember a mystery novel ever featuring so many diagrams.

So yes, I enjoyed "Sekikyuujou" Satsujin Jiken a lot. It's a very worthy entry to the series. I do think the previous books each had a more memorable major "key" moment that was absolutely insane, from the reason why people were getting decapitated in Clock House to the reveal of the identity of the killer in Alice Castle or simply the presentation of certain locked room murders: in "Sekikyuujou" Satsujin Jiken however does something what I haven't seen Kitayama do before, by utilizing the idea of a series of locked room murders with actual meaning in a novel, and I think the book does show Kitayama's growth as a writer across two decades because it's a very consistent mystery novel throughout, with no real lows and it's entertaining from start to finish. Definitely one of the must-reads of this year!

Original Japanese title(s):  北山猛邦『「石球城」殺人事件』