硝子の塔の殺人 🗼 (ABC) Week 7

硝子の塔の殺人 :tokyo_tower: Week 7

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Week 7 October 11th, 2025
Chapter(s) and sections 三日目: 2, 3, 4
Start page 311
End page 342
Page count 32
Previous week week 6
Next week week 8

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Character names (p.6)

Full Name Occupation Room
神津島太郎こうづしまたろう 館の主人 壱の部屋
加々見剛かがみつよし 刑事 弐の部屋
酒泉大樹さかいずみたいき 料理人 参の部屋
一条遊馬いちじょうゆうま 医者 肆の部屋
碧月夜あおいつきよ 名探偵 伍の部屋
巴円香ともえもどか マイド 陸の部屋
夢読水晶ゆめよみすいしょう 霊能力者 漆の部屋
九流間行進くるまこうしん 小説家 捌の部屋
左京公介さきょうこうすけ 編集者 玖の部屋
老田真三おいたしんぞう 執事 拾の部屋
Illustrations before the prologue

Participation

Will you be reading along with us this week?

Will you be reading with us?
  • I’m reading along
  • I will catch up later
  • I’m still reading the book but I haven’t reached this part yet
  • I’ve read this previously but I’m here for the discussion
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5 Likes

I only started reading this chapter, 15 minutes, but I have a crazy idea.

What if it is indeed a person from an empty cell, and they didn’t run away because it was the serial killer from 13 years ago themselves? And if they called the police, he could be sent into jail for life or worse.

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It may be only artistic licence but it’s not possible for the blood stain on 円香’s dress to spread if she doesn’t have a pulse….

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Week 7

The picture from chapter 4 for our audio book friends!


(was there any attachment to the audiobook so you could see it? or any description? just curious)

I was sure that there would be some reveals and some twists and some more action but nothing much happened in the first two chapters of the assignment…
At least at first glance. 遊馬 didn’t ask the rest of the people if 月夜 was with them when they heard him falling, so it can still potentially be her. Also looks like 月夜 drugged 遊馬 so he had a good nap. But those things being only slightly suggested and not said explicitly, could also be a trick from the author to deceive us.
For me the most suspect thing is that 月夜 took a shower. I’m thinking that there’s something behind it, as in the need to clean up the blood from another murder or something.
Also when 月夜 asked for the 聴診器, I thought, “ah, finally they will check if the dead people are actually dead”, but nope, it was for the safe. (though I guess you do need the key from the safe first, to get access to the rooms where the dead bodies are, so that could still happen)

That being said, after reading the third chapter (chapter 4), I finally have no doubt than the dead people are indeed dead. (when they entered 神津島’s room I wasn’t sure what they would find, him waiting for them smiling, or the body gone, but didn’t except that the dead got killed again haha).
Breaking the 4th wall to ask us who do we think the criminal is, is very meta (Furuhata Ninzaburo does that, Columbo too? and maybe others).
I have no idea, but I’ll try to think about it..

I think that’s a good theory. The first time they told that story and gave us his name, that made me sure that he / they would have a role in the story at some point, otherwise could have been fine to just mention the story without a name.
But I also still think that it makes more sense if they are here among the guests rather than hidden in the tower and that we haven’t seen them yet.
And then again I’m back at the contradiction of why would they need to torture 巴 if they already know about the basement..
Tough case really, I hope the reveal will make sense!

6 Likes

That was an interesting read! I still don’t see Tsukiyo as a culprit, and I still have Kuruma as a main suspect, but I don’t have a strong case against him.

Anyway, even though the book started with Yuma being caught, I still somehow wish he’ll get away with it. You know, when you rewatch or reread something you hope the character won’t do a stupid thing this time :sweat_smile:

Yeah, I actually think the same. And if it would be someone from the guests, I’d be happier with the book. Otherwise it feels a bit like cheating.

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I should have asked this week one but what’s the reading of 名探偵? なたんてい or めいたんてい or みょうたんてい? I’m thinking the second one but I’m not sure.

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めいたんてい is the reading

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Not a bad idea, although presumably a lot of time passed between him disappearing in the woods and the tower being built, how would he have ended there in the first place?

Also from a mystery novel plot construction perspective, having the murderer be completely unrelated to the members of the “closed circle” wouldn’t be very フェア.

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Yay, I finished this week as well :smiley: . Was a fast one

A little said that the theory from last week that 月夜 took the master key was apparently not true? Or maybe it was another diversion, and she had it all along, since she was the one who took it out of the safe?
I also didn’t much like him taking the pill case again. Now it’s on him and will for sure lead to some incriminating moment, me thinks. I mean, we still have a good chunk of pages left, even though we are told the mystery is already solvable ^^

I was thinking the exact same. I half expected 神津島 to be the murderer of the other two. Although, I couldn’t tell you a solid/coherent motive ^^

At least we now know that we “could” solve it. It’s a nice motivation for me to think about the 暗号人形s this week a bit. Maybe I can get something out of them.

The only thing that also sticks out to me at the moment is that all three were stabbed through the heart. It has to have SOME significance, I think.

I don’t remember him getting caught, he was stuck in the 展望室 and lamenting he shouldn’t have gotten close to 月夜 but that is all. Maybe he thinks he is exposed in that scene (don’t remember clearly), but that could be just him misreading the situation as well… he isn’t the smartest of our characters.

The book has a pretty good reception. I’m keeping my hopes up.

9 Likes

I tried to decipher the message, but didn’t get very far. There are just four types of people, so we can use numbers instead of them, it’s easier that way:

My picture and initial guesses


I’m thinking that groups of three symbols correspond to one letter, and it should be English text, given the O (or 0?), U and B letters that are revealed. But since there are only two pairs of equal trios, this seems tough…

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Interesting, I hadn’t paid too much mind to the legs and arms directions and saw only two kinds of people.
Which would make a binary message, which could be easier to translate maybe..

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When a chapter is particularly long like last week I make sure to dedicate time to finish it, and generally manage to go through the entirety in a few days, but this week is pretty short so I think “oh it’s going to be fine I can take my time” and now it’s Thursday and I still have one third to go.

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And next week is not going to be giving you a break either, ouchie

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w7

Yeah I was wrong about that, but then that also makes this entire safe thing rather pointless. Disappointing. I wonder if it will come back.

Yeah that’s like him running up the stairs alone last week: what’s the point? If I was him I’d stand by and play it cool. Given the magnitude of the situation it feels like his original murder is almost irrelevant at this point. Get rid of the case and move on.

That would be very little info. I too think the shape of the arms and legs is significant. That said I have no idea what it could mean. I also have no clue who the murderer is, but here’s my top 5 suspects by gut feeling:

  1. 九流間
  2. 夢読
  3. 加々見
  4. 左京
  5. 月夜
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Since we seem to now be reaching the conclusion, I decided to re-read the prologue because I remember being generally confused by it originally. In hindsight I think what led me astray is that the narrator does this thing of suddenly switching to 俺, which led me to believe that there was a 3rd person (besides 遊馬 and 月夜) involved. Maybe that was on purpose…

Oh and regarding the dancing figures, maybe the shape of the message is relevant? It’s oddly formatted. I tried a bit longer to decode it but without success.

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Nice, I’ve been thinking about going back to read the prologue too. It has got to be happening soon. I was actually thinking that that might be what this week starts, considering how last week ended.

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Week 8 is up :slight_smile:

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A challenge to the reader is very standard in golden age detective fiction (particularly in Ellery Queen novels), and not uncommon in shinhonkaku. Absolutely no surprise that Tsukiyo would give one.

Tsukiyo is the one who put the key in the safe and took it out, so I think it’s still possible that she had the master key the entire time. Which doesn’t fit with her solving the case, but… it’s possible that she killed Oita and Tomoe and is going to pin the murders on someone else. So she really does view Yuma as her Watson (but to her Moriarty, rather than Holmes). In terms of her creating a mystery just to solve it, that could be it, but she didn’t want to kill anybody innocent, so she chose three people who ‘deserved’ it (and learned about it from the escaped prisoner, as lifev suggested, or somethin?).

I agree that the message looks like groups of 3 figures (each probably being one letter), can’t be bothered to try harder than that tho.

For the prologue, I don’t remember the exact wording, it seems like he def gets trapped in the collection room, maybe he wasn’t exposed as the murderer but Tsukiyo just tries to kill him to tie up a loose end and he escapes into there or somethin’? We’ll find out soon enough I suppose…

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substitution

Not that it changes anything really, but the bottom one in your picture is 233 not 133 I think

I had a try myself with the cipher, couldn’t really get anywhere. I looked up the original Sherlock one (since 遊馬 knew about it, I think that’s fair) here The Adventure of the Dancing Men - Wikipedia
And as expected, it was just a substitution cipher. But there was more to work with in sherlock holmes’ one, so it was easy to work out where E was etc. through frequency. But here there’s not enough, and only 2 repeated things only repeated twice, neither of which look like they could be E really if it’s English.

My guess is that third row and fourth row could be
OUT
OF
Which would make sense, but not sure how that then connects to everything else.
Fifth row could be “humble”, but then M at the start doesn’t make sense.
Maybe it’s not English, but Japanese in romaji anyway, but then it would be very short. B being there shows that it’s not kana substitution at least.

General

I liked having a shorter chapter to help catch up a bit. Especially when it was even further broken down. I’m still pretty sure 月夜 is behind everything, her showering like Akashelia said, her not being seen by the others when 遊馬 was pushed down the stairs, the fact she wants to go snooping around the crime scenes, I think she’s involved in it from the start.

Thought about 神津島 getting stabbed through the heart - surely it’s just to dress up the murder and make it seem connected to the other ones, as if it was done by the same person? If most of the remaining people who know it was a poisoning get killed off from now, and then the bodies are left as they are, maybe it’s intentional to draw attention away from the poisoning, and thus 遊馬. Not sure why someone would do that. Maybe 月夜 wanted to murder all 3 of the residents and doesn’t want 遊馬’s murder getting in the way of that. But then, why would she want to push him down the stairs? It seems too risky as a way to temporarily take him out - she could have just slipped him a sleeping pill in an easier way or something. If she wanted to kill him it wouldn’t have been a good way either. It’s just way too risky. Anyway I don’t think I’m capable of going back through everything and figuring out the mystery for myself, but appreciate being told that it’s possible. Instead I’ll just go through to next week and see how much of it hits.

Also something surely happened to 円香 after being “murdered” the first time. There’s a stun gun involved somewhere in some of these murders…

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Wouldn’t it be strange to have one O in cleartext and the other in cipher?

I wonder if it’s not a substitution at all and it’s all just a red herring.

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