[DeepL Translation - needs review] Introduction to Volume 1: The members of the Eito University Mystery Novel Club, including Director Egami and Arisu Arisugawa, arrive at the Yabuki Mountain campsite for their summer training camp, only to find an unexpected situation awaiting them. Yabuki erupted, and the three groups of students who happened to be together were instantly trapped in the campsite, which had become an isolated island on land. In this extreme situation, a killer appears as if...
If I say "this is a 1980s closed circle murder mystery involving college students, a mystery club 名探偵 character, and classic 'challenge to the reader' to figure it out yourself before the big reveal, and oh, a smattering of random (somewhat difficult) side discussions about weird things people think about the moon" and you go "wow that sounds great!" this book is probably for you. If you instead think any of that is tedious or tropes you don't like then this book is not for you, turn back now. My glowing review should mean nothing to you if those are not things which delight you.
OK with that out of the way, I adored this book. It's a lot like 十角館の殺人 in many ways, but the cast is bigger, the setting wilder, and the conversations frankly a bit more out there. You'll understand when you get to the moon bits.
For grammar, well, expect tons of Kansai dialect and idioms to trip over. Vocab? Brace yourself but it was a fun ride! Definitely a nice vocab stretch here, even discounting the idioms. I probably did more googling with this book to understand references being made than I have in a long while. Was it strictly necessary to understand the story? Nah. Did it enhance my enjoyment of it? Yes.
I'll note that the audiobook has an interesting recording style. Every single character seems to have a dedicated actor from what I can tell, but the recording doesn't sound at all natural. It was a bit jarring at first. Once I got into the groove of it it was fine, but be aware if you're picky about audiobooks that there is something somehow off about the audio mixing.
Overall, I plan to read more from this author and think this was a great introduction to his works