It would have been cool if an iron fan had been used as a murder weapon...
Disclosure: I have translated Arisugawa Alice's The Moai Island Puzzle.
The latest entry in the Himura & Alice series (AKA the Writer Alice series) has an interesting title: when Ellery Queen's The Door Between was first announced to serialize in Cosmopolitan, it somehow was reported in Japan that the story would be titled The Japanese Fan Mystery, and it is a title that has always stuck with Japanese mystery fandom, even though it was not true and there is of course no such Ellery Queen novel. This story starts with Alice being asked by his editor to write a story with that title, and gives him a lot of reference materials on fans, and we first see Alice struggle with all kinds of ideas that involve fans, like locked room murder tricks that use fans. And none of them are really good, to be honest, though that's the joke of course. The actual story is connected to fans because Souichi had a beautifully illustrated Japanese fan in his possession when he was found, earning him the John Doe name "Mr Fan" for a while, but it is a bit of a shame the actual object isn't really "used" in the mystery plot.
The mystery thus revolves around a murder in a locked annex, as well as the mystery of Souichi's disappearance, and the question of why he had lost his memories and what he had been up to in the last six years or so since he ran away from home. That said, it should perhaps be noted that unlike the very mystery-plot-focused books in the Student Alice series (disclosure: I translated The Moai Island Puzzle), the Himura and Alice series usually have more room to be a bit more character-introspective, and that is certainly noticable in this book, where a major portion of the book is dedicated to hearing the thoughts of all the family members and other related people on Souichi, both how he was as a child to how they think they should approach Souichi now he has lost his memories, and their views on how to move forward into the future. Personally, I have to admit I found the book to be moving a bit too slow, but Nihon Ougi no Nazo will probably entertain people who are into the human drama aspect of someone suddenly disappearing for years, and then coming back as a different man. Some parts are great in characterization, while mystery-wise, you could easily just not have them, and still have the mystery work. I know I am slightly more extreme when it comes to 'minimalist puzzle' mystery fiction, so I assume other readers will find these segments far more interesting (and I wouldn't even say I found them dull, just a bit long).
When the story returns its focus to the questions of who committed the murder in the locked annex, and where Souichi has gone off to now, we are treated to some great deduction scenes we have come to expect from Arisugawa. Interestingly enough, Himura himself does say that while he usually goes for truth borne from the logical inferences based on the evidence, this time we have Himura almost turning things around, coming up with a theory that can be supported by the evidence they have, but which ultimately is difficult to stand indepedently as logical proof, because so much of the background of the case is left in the dark. That said, the way Himura logically shows who the murderer is, is really good. Unlike a really cool locked room murder trick, it's kinda hard to explain "clever" lines of deduction and what makes them so good, but I really like the one here: Himura pushes his deductions to answer a question which seems very trivial at first, but the logical implications of this conclusion allow him to determine who the killer is, and it's this jump from what seems like an inconsequential deduction, to suddenly solving the whole case, is great. Nothing beats the one deduction line from The Moai Island Puzzle, of course (that one is... unbeatable perhaps...), but if you like that one, you're sure to like what Arisugawa does in this one too, though the set-up is far simpler (just a disappearance + one murder). Oh, and don't expect too much of the locked room murder, as always in these Queenian stories, it's more the why that is used in clever ways than the actual how. There is a hidden tragedy that is unveiled as Himura explains how and why the murder was committed, and it is here Arisugawa does a great job at connecting the 'story' of Souichi and his family to the core mystery plot, presenting a sad, ironic tale of death that was lurking beneath the surface.
This story was serialized in Mephisto starting in 2023, so some time has passed since the height of the pandemic, and Arisugawa (the author) does bring it up quite a few times as the story progresses, with little comments how not long ago, they couldn't even just go out to eat normally and things like that. It's interesting how references like these really "date" the Himura & Alice series, and like The Simpsons, shows that these characters (and their surroundings) are "timeless", as they haven't really aged since the first book (46 Banme no Misshitsu) and that came out in 1992 and now they survived the pandemic! Interestingly enough, Nihon Ougi no Nazo is actually touted as the book written to celebrate the 30th anniversary of the series (how many modern mystery series do you know that have been running for so long?!), though its serialization started a bit late. But that is also why this book was released in two versions, one regular pocket, as well as a luxurious hardcover.
I happened to have re-read the first novel a while back, so that made the changes in Arisugawa's style in over thirty years rather obvious, but as a whole novel, Nihon Ougi no Nazo is a far more complete work, with a dramatic tale about a young man who lost his memories, and his family coping with that realization, with a locked room murder mystery forcing everyone to readjust once again. The core mystery, while limited in scope, offers Arisugawa to show off once again how great he is at impressive lines of deduction that start out from seemingly innocent clues but then are nurtured into brilliant logical proofs that point beyond any doubt towards one culprit, but it does take a long while to get there.