硝子の塔の殺人 🗼 (ABC) Week 6

硝子の塔の殺人 :tokyo_tower: Week 6

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Week 6 October 4th, 2025
Chapter(s) and sections 三日目: 1
Start page 253
End page 310
Page count 58
Previous week week 5
Next week week 7

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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?

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5 Likes

Am I the first finisher this week?? I did read for many hours today, really wanted to finish this chapter!

Week 6

The chapter started as usual, a lot of talking, a predictable death, a lot of talking. But then not nothing happened suddenly, the discoveries in the hidden basement were huge!
Both that the victims from the murders (and the culprit?) from 13 years ago were here, and the laboratory to test humans.
I definitely think that we have a victim on the loose, taking revenge on their tormentors.

Theory time:

  • Had a thought when they started talking about 中村青司 and burning the screen to uncover the secret passage. Possibly it’s not the only secret passage of the tower, and now maybe the layout of the tower makes sense to me, as in why is there so much free space between each room. Could totally be another 螺旋階段 there, allowing for a murderer to go without being seen as they please!

  • I feel like there was also something about 神津島 telling that he had prepared something for the group, so I’m thinking it was his idea all along to have them resolve a “real” mystery. Even though he died, the things he had planned with 巴 and 老田 are still happening and are a test for the other guests. Since 神津島 was killed himself by 遊馬, we don’t know that he was supposed to be killed too by the same murderer and maybe he had plotted the whole thing. Either alone or with victim on the loose / their parent.

  • I’m having a hard time seeing 月夜 as the killer anymore but I still think that there are so many weird things with her, that she had an alibi at each exact murder’s time, that she was always the first on the scene, for example finding the key to 巴’s room or checking outside of the window… We’ll see…

7 Likes

You’re definitely fast! I think I’m about 2/3 through this chapter, and today has been the day I’ve read the most so far, I feel like the pace is really picking up and I’m really excited to see how it’s going to develop! Can’t wait to finish and discuss with everyone here.

8 Likes

I didn’t time myself and had several sessions but all in all I think that it took me 4 or 5 hours, so probably not the fastest pace!

8 Likes

This chapter was the most dynamic and captivating so far! I have an urge to read further, but I’ll try to resist…

The revelation about the hidden lab was just wow. I didn’t like Koudzushima in the first place, but now he became basically a serial killer and torturer. And my compassion for Oita and Tomoe is gone.

After Tsukiyo’s gloomy upside at least I feel her as a human being with feeling.

From Yuma’s perspective, I think it would be better for him to get rid of the poison and not start cheering up Tsukiyo. That way police never connects the dots, Tsukiyo might stagnate in her investigation, he has an alibi for 2 murders out of 3.

I’m really bad at solving detectives, and I have no idea who is the murderer. I suspect the most Kuruma, because he was very quiet when they discussed the case of 13 years ago and didn’t behave in a way so that I’d thought “it is definitely not him”. Others I don’t see as culprits.

As for someone from the open cell, it would be really lucky for them to survive all this time and not being noticed. Unless somebody like Tomoe secretly helped them.

That sounds plausible! And maybe there are some technical entrances to the rooms as well.

9 Likes

Oh that’s funny, he’s the only one I don’t see as a culprit xD

I also feel like something needs to happen with the power room.

8 Likes

The more I read, the more I think Tsukiyo is the killer. Kagami seems too obvious, and her whole speech about what being a great detective means, solving crimes or preventing them, seemed completely out of character; also, setting up some form of Munchhausen by proxy… Though in the end… I wouldn’t be surprised if all of them were killers, each for their own reasons. This whole set-up screams classic Agatha Christie for me, and I’m really surprised she hasn’t been mentioned more

8 Likes

I haven’t finished this week yet; I’ve just gotten to the part where the group discovers the hidden staircase in the home cinema. There’s going to be some really weird reveal with 月夜, I’m sure if it. I’m almost wondering if she has a split personality. Her high/low moods and how one seems aligned specifically with mystery trivia, how she kept changing how she referred to 巴円香 (巴 vs 円香). I wish I was paying more attention to how she addressed the previous victims…

7 Likes

Very kind of the murderer to add furigana to their blood message.

8 Likes

I was 100% sure I had read to the end of this week’s assignment…. Except I hadn’t :sweat_smile: ! Now that I have, I’m 150% convinced 月夜 is the killer, and she pushed 遊馬 in the staircase. In this context, 「だから俯いていないで、君がいまやるべきことをしよう。本当の姿を取り戻そう」is a very dangerous thing to say (and 月夜’s reply, 「私のやるべきこと…。私の本当の姿… 私はどんな状況であっても、自分自身の役割を全力で果たさなくてはならないんだ」 is chilling) !

8 Likes

whoops (got any stock picks?)

can’t believe the nazi sympathizer was evil smh my head

Yuma continues to be awful at everything he does. Searching the exhibition room really shouldn’t be necessary since it can’t be unlocked from the inside, so if someone did go hide in here (and the exhibition room was locked, which it apparently was) they wouldn’t be able to get out (without an accomplice or secret passage). idk why yuma is so puzzled by there being someone when it could’ve easily been kagami or sakaizumi who went into their room. Or, if there’s a secret passage in the empty space, it could’ve been anyone (altho it would depend on exactly where the secret passage opens up).

8 Likes

:joy: Yeah, never listen to me, I’m awful at mysteries.

6 Likes
This week

This chapter was great, I was already excited reading about the basement, but we also got some characterization AND something mystery happening at the end!

I am doubting a lot who is behind the murders now. In the beginning of the chapter, I was betting on Tsukiyo. Then came her backstory, which led me to wonder, is she so calculating to the point of feigning her disappointment at herself just to trick Yuuma/lower his defenses? At the same time, the author seems to be hinting a lot at an unknown survivor being the one behind the murders, but doesn’t that make it too ‘obvious’ then? I am definitely thinking it will be a multiple murderers kind of situation, or perhaps 2 people cooperating (one of our known characters + a/the mysterious unknown survivor, who happens to be their acquaintance). If this is the case, I’m leaning towards Kuruma or Sakyou (or maybe both are working together? They are always hanging out at the entertainment room just the 2 of them…)

There was definitely also some deja-vu when I was reading the ending, when Yuuma mentions his own deja-vu. I feel like I’m missing something here, but I suck at solving mysteries which rely on hidden rooms and things like that (I can barely understand the illustration of the building and already gave up on the whole door mechanisms, lol).

8 Likes

More than that, it doesn’t make any sense, at least if the survivor isn’t one of the guest. If you had been sequestered by a madman, and had escaped, hidden in the basement for God knows how long, would you wait precisely for the moment when the house is full of guests, especially guests knowledgeable about mysteries and crimes, before killing the 3 persons who actually live here full-time ?

8 Likes
Reply

Another thing that doesn’t work with the survivor being the culprit, is that they know about the secret dungeon, but apparently Tsukiyo is 100% sure that the maid was tortured in order to reveal where it was.

7 Likes
Reply

These are both great points to consider. I do think there is a large chance the survivor ‘escaped’ and somehow returned as one of the guests (which would also explain how they are able to move around more stealthily, as they know at least one secret passageway within the house). But that does contradict the point that Akashelia raises.

I think it’s starting to click for me that there is another passage, and that this is the deja-vu that Yuuma feels at the end of the chapter. It would explain how they can hear the footsteps of the culprit (?) without seeing them, and how he didn’t notice someone coming from behind and pushing him down the stairs.

7 Likes
W6

月夜 totally snatched the master key when she (uncharacteristically) rushed to help 酒源, right? The author established that she was skilled at this, and then the whole locking of the safe took place really quickly without anybody double checking what was put inside exactly. I say that she traded her key with the master key just before it was put inside.

She could also easily have faked hearing someone eavesdropping. I mean why would you scream “who’s there” instead of just opening the door to surprise them in the act?

Also why does she feel so badly for failing to save 円? She was complicit in unspeakable acts of torture. Good riddance. 月夜 seemed completely unphased by the previous murders.

Also this is not plot-related but are there no sprinklers in the cinema room? Burning the screen in an enclosed space like this must have been messy. Just cut the screen next time… I guess burning it looked cooler.

Regarding the discussion of hidden pathways, there’s definitely a lot of wasted space in the architecture as it stands. Then again if it just invalidates all we know about the various doors and the various keys and locking mechanisms, it feels a bit cheap as a twist. “The solution to the locked room mystery is that… there was another door nobody noticed. Woops.”

I considered that as well, that every murder was a different killer for a different motive. We don’t really have any motives for anybody besides 遊馬 however…

Yeah that bothers me too. What even is the point of running through the stairs in the first place? 遊馬 himself hid in his room when he was being chased. He should be familiar with the concept.

8 Likes

Week 7 is live :slight_smile:

6 Likes

Ha, finished this week right on time. It was a super busy week, but I still managed reading the part :smile: . For next week’s discussion, I’ll be more timely again.

Yes, exactly that. This chapter was huge in giving her a little more characterization compared to just being crazy about mystery novels. At least I can see how it happened now.

She definitely could use some proper counseling :smiley:

I read your comment at the beginning of this week, and kept an eye out. I think she always referred to her as 巴 and 遊馬 always referred to her as 円香

Interesting interpretation at least :exploding_head:

Uhh, I like that, would have not thought much about the scene without your comment. Good idea.

If we assume she was only going off of the blood message, it specifically said to kill 中村青司. He died in a fire in his house. So I see why burning it would be the logical conclusion. On the other hand, she said she expected a secret passage so :person_shrugging:

I’m a little bit nervous that his room had the door open and he was out for several minutes while investigating. Nobody knows what could have happened in the room. Poison still there? Any incriminating evidence being planted?

I’m also a little surprised they all instantly jumped to the conclusion that the murderer must have the hidden cellar prison / experiments as the motive. It sounds plausible at first, but how did the murderer get knowledge of the prison is the 1 million dollar question? How did they obtain knowledge about people being kept there?
And the motive also assumes that 神津島 was not killed by 遊馬, which should make him at least doubtful of the motive.

6 Likes

Well done! It was a long one.

5 Likes