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第15回MF文庫Jライトノベル新人賞《最優秀賞》受賞作

「君、私の助手になってよ」
四年前、地上一万メートルの空の上で聞いた台詞から、俺と彼女の物語は始まり――終わった。

俺・君塚君彦は完全無欠に巻き込まれ体質で、謎の黒服に謎のアタッシュケースを持たされたあげく、ハイジャックされた飛行機の中で、天使のように美しい探偵・シエスタの助手となった。
それから――
「いい? 助手が蜂の巣にされている間に、私が敵の首を取る」
「おい名探偵、俺の死が前提のプランを立てるな」
俺たちは、世界中を旅しながら秘密組織と戦う、目も眩むような冒険劇を繰り広げ――

やがて死に別れた。

一人生き残った俺は高校生になり、再び日常というぬるま湯に浸っている。
なに、それでいいのかって?
いいさ、誰に迷惑をかけているわけでもない。
だってそうだろ?
探偵はもう、死んでいる。

328 pages, Paperback

First published November 25, 2019

36 people are currently reading
340 people want to read

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二語十

20 books

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5 stars
71 (28%)
4 stars
65 (26%)
3 stars
65 (26%)
2 stars
33 (13%)
1 star
11 (4%)
Displaying 1 - 29 of 29 reviews
Profile Image for Laura A. Grace.
1,966 reviews306 followers
June 27, 2021
This was a surprisingly very good read!

And I say surprisingly because I struggled reading at first because I had not realized this was a light novel and not a manga. However, once I got sucked into this story, I absolutely loved the combination of genres and how this was more than just a mystery! There was a depth to each of the characters that I wasn't prepared for and many good one liners that struck a chord with me such as:

“If you’re nobody yet, that means you can become anybody you want.”

I was also extremely excited to realize how the cover plays a role within the story and how it all came together. Having a story centered around their "not" being coincidences and memory transference was genius! It was such a hook, line, and sinker as I realized how deeply that plays a role in this story. Plus, when you have some really lively characters, it makes for good humor, action, and growth.

The Detective is Already Dead is a very fun ride, but also a moving one. There was a realness on page that is woven into every word that captured me and think reading the Afterword made it all the more compelling. I would be very curious to know what happens next!

*(I received an e-copy from the publisher. All thoughts expressed are my own.)*
Profile Image for Genma496.
81 reviews10 followers
December 5, 2022
This book is so incredibly disappointing, and that's precisely because the premise had so much potential in the first place. For a mystery story, the idea is great. The main character, the assistant, whisked away on a whimsical three year crime solving adventure, has to return to his boring normal life, using the knowledge gained on his journey from the deceased great detective to solve new cases while meeting new friends and grieving the death of the one he idolized. It sounded like it could've been amazing, but unfortunately, the author clearly had no interest in writing a mystery story.

This first volume has the structure of a mystery story, made up of three self-contained cases that Kimihiko, the protagonist, has to solve. Unfortunately, none of these are anything that you could remotely call a mystery in any sense. The first case is so completely obvious that it hardly counts, the second case is the closest to what you'd call a mystery, but it can hardly be said to follow any principle of fair play, and the third case just ends up being an action story against an enemy brought up out of nowhere and without any foreshadowing. If you're writing a mystery story, making the main antagonistic force be a big secret shadowy organization is a peculiar choice. If you do that, then no matter what the case may be, the audience can just assume that the culprit works for them. That's the entire question of motive out the window. Okay, but then you can have the mystery be which one of the cast is the organization spy! Well, the problem there is that the cast of this story is minuscule, each chapter basically introducing only one new character. If you have no why and no who, well, I won't say it's impossible to write a mystery, but it sure seems like a tough job. Well, I doubt such considerations ever entered the mind of the author though. The narrator even apologizes to those who expected a regular mystery story, but the worst was when Siesta claimed that "a great detective solves a case before it even begins" or somesuch. No, just no. In the afterword, the writer says that that he intended this story to be a blend of genres, but I don't think that's what this ended up being at all. It *is* possible to mix mystery with other genres, and hell, you can even make a supernatural mystery, but that kind of thing requires being very careful about introducing rules and foreshadowing and limitations, and the frustrating thing is that this story doesn't even try. In the end, all this is is a supernatural action drama, with any mystery elements just being window dressing, like the salt and pepper on this generic light novel steak. And that's just a shame to me, as a mystery fan who bought this book entirely with that expectation.

But whatever, enough judging what this book isn't, let's judge what it is. The characters are all relatively likeable, even if the "witty banter" they exchange can sometimes feel incredibly forced, and there's even a little charm to the relationship between Kimihiko and Siesta as it's portrayed (maybe because it was ripped off from Nisio Isin's Boukyaku Tantei series, down to the characters even looking almost identical, but whatever.) Indeed, the sole bit of honest authenticity I can sense in this book has to do with the feelings of melancholy and grief that the main character feels over Siesta's death, and his feelings of inferiority and inadequacy regarding that. If the story had been written in such a way as to really delve into those emotions, but unfortunately, it spends too much of its time failing at everything else. The first chapter, despite being terrible as a self contained mystery short story, is pretty good as far as set-up for the series goes, with Nagisa inheriting Siesta's heart and some of her feelings. It's a little corny and predictable, but I can accept it. But the second chapter, while introducing a character that is pretty likeable, doesn't really further that in any way. And the last chapter attempts a story arc that is simply way too ambitious for a book with only 200 pages. As an idea, Siesta resurfacing one last time from within Nagisa's heart to defeat the enemy that killed her and properly say goodbye to Kimihiko, that sounds like it could be an incredibly cathartic moment. And indeed, sap that I am, I can't deny feeling a little happy reading the two's banter while they fought together, but unfortunately, the buildup just isn't there. For one, it would have been way better to save revealing the way that Siesta died and the enemy that took her down for a later volume, because as it is, it seems like the character set up as an incredible, extraordinary genius in both combat and intelligence was defeated by some random long-tongued fucker with zero memorable lines and the same amount of presence whether he's invisible or not. It's just a waste of a potentially great conclusion to an arc, just blowing its load too early.

All in all, The Detective is Already Dead turned out to be a huge disappointment. I wonder if Byouinzaka Kuroneko was right in 2008 when she said that light novels and mystery just don't fit together. I'd like to hope otherwise, if purely for the shallow desire to have more good mystery series with good illustrations on my shelf.
This entire review has been hidden because of spoilers.
Profile Image for Rebecca.
4,310 reviews69 followers
July 20, 2021
This was...a thing. I could see it genuinely trying, but it ultimately came off as thinking it was a much more clever mash-up of genres than it was, and almost all of the characters were kind of annoying. Better than the first episode of the anime, though.
Profile Image for Mark.
2,795 reviews269 followers
July 7, 2021
Kimihiko has been a trouble magnet for as long as he can remember. One day this leads him to fall in with Siesta, a self-proclaimed ace detective on a mission. That was a long time ago, however, and the detective is, in fact, already dead. Kimihiko’s life has apparently gone back to normal, but the past isn’t the only thing that won’t stay buried…

Adjust your expectations immediately - though there is some cleverness to be found in this book, it is not a detective story in any sense of the word you might be expecting. Siesta explains her title over the course of the book, but it’s definitely not a classic mystery (even with name checks to Kindaichi AND Conan).

What we get instead is a monster fighting team that wouldn’t be out of place in a shonen manga. And you know, mixed in with some light romance and decent action, with a smattering of clever planning and deductions, it’s not all that bad. Nothing that would blow your socks off, but won’t send you screaming for the hills either.

It starts off with a great set piece on a plane and then flashes forward to the present, where Kimihiko is trying to live a boring life for a change, which goes about as well as you’d expect. Faster you can say ‘boobs mashed into your face’ we are off and running as a gaggle of girls assembles around our erstwhile former assistant (this part is 100% the nadir of the volume).

Despite all that, plus appearances from an idol and a very likely tsundere, there’s nothing yet by way of a harem, exactly. In fact, this book is a little (not too much, mind, see: boob mash) more mature about its relationships and ‘relations’ than you’d think. Probably because it’s currently laying out one of the weirdest love triangles I’ve ever seen. There is also a hilarious flipping off to a prospective chance at fanservice that I got a good chuckle out of.

Of the various plotlines, the idol story is actually pretty good and there’s a really fun misdirect that’s played for laughs but shows that Kimihiko picked up a few tricks from Siesta along the way. I initially assumed that this was all going to turn into a story of Kimihiko working through his grief and becoming an ace detective himself, but I think this book’s oddly suggesting that some people are just born followers whose strength lies in supporting those around them.

The last story is set aboard a ship and fleshed out a lot of the characters, but the actual plot is a little thin because once you realize the nature of the MacGuffin it becomes an exercise in tedium waiting for the book to get there. I do like the ending, that all said, but it gets a little ‘the real treasure is the friends we made along the way’ for my liking.

The author’s heart is in the right place - they wanted to write something they liked and I think that shows. If it isn’t the most clever book ever in word and in deed, well, at least it’s trying its best the whole way and I do think that comes across. Not every attempt knocks one out of the park, or in some cases even makes it over the plate, but the book always has something else to try.

It certainly won’t be for everybody. The dialogue is pretty par for the course, so the banter tends to lack much snap, and the whole futuristic aspect is absolutely crazypants. It’s heavily focused on fancy, elaborate fights and some scientific concepts that are about two shades away from quackery (or a b-grade horror movie).

3 stars though. Once I got over what I wasn’t getting and focused on what I was, I had a better time with it. I’ll definitely pick up another volume, if only to simply enjoy having one more light novel on my list that isn’t yet another bloody isekai.
Profile Image for Librarian Jessie (BibliophileRoses).
1,723 reviews87 followers
August 21, 2021
This is another case of intrigue, but ultimately I did not find myself as enthralled as I would’ve hoped. ~ It’s not poorly written. However, I did find myself confused at times and ultimately I didn’t enjoy it as much as I hoped to.
Profile Image for Alex.
12 reviews
October 21, 2021
A Wonderful book that I couldn't put down! I can't wait till the second volume! Everyone should give this story a try in my mind.
Profile Image for Iroha Miyumi.
122 reviews9 followers
April 4, 2021
一年前に高校三年生・君塚君彦は探偵・シエスタの助手ですが色々があって彼女が死んでました。その時で、君彦くんはこの仕事を受け継ぎじゃなくて、普通高校生として、過ごしました。その筈ですが、君彦くんは特別な体質です。彼は必ずに、不幸なエベントが巻き込みばかりです。例えば、裏道で、偶然に彼は白い粉の取引を目撃さて、偶然に殺人現場に居て、などなど。そう、彼は探偵の助手が引退ですが、彼の体質のせいで、彼の危険の日々が続きました。過去の経験のおかげで、彼は必ずに、事件を解けますので、彼は有名人になりました。

ある日、君彦くんは夏凪渚に会って、彼女の強引的のせいで、彼は彼女の依頼に受け付けました。色々な理由があって、渚さん彼女の心臓のドナーに会いたいです。その為に、彼女は彼の協力が欲しいです。彼はその通りに応じましたが、亡き探偵・シエスタの関係あるみたいです。「探偵はもう、死んでいる」ので、彼女が生き残し筈がないでしょうが、彼女の不思議過去は君彦くんの現在に間違いなく影響します。
ーーーーーーーーーーーーーーーーーーーーーーーーーーーーーーーーーーーーーーーーーーーーーーーーーーー
キャラや世界設定はとても面白いので、僕はこの小説が気に入ってた。各々キャラは魅力があるので、気に入ってキャラが多いです。ストーリーや展開は面白いですが、この小説はミストリーじゃなくて、SFです。個人的に、僕は構いませんが、他の人はこの点を構いますかもしりません。元々、あまりミストリーが読まないので、この点関して、期待がしないです。

気に入って方は是非おすすめます。


One year ago, Kimihiko Kimiduka, a fourth-year (3rd) high school year student, was the assistant to the detective, Siesta, but a lot of things happened and she died. At that time, Kimihiko didn't continue on with her job but chose to live normally as a high school student. That was supposed to be the case, but Kimihiko has a special body condition. Without fail, he will get dragged into unlucky events. For example, at a backroad, he saw a cocaine drug deal by coincidence, happened to be there at the murder scene, etc. So, while he did retire from being a detective assistant, his dangerous days keep continuing because of his condition. Thanks to his past experience, he solves any case without fail, so he became a famous person.

One day, Kimihiko met Nagisa Natsunagi and was forced to accept her request. For various reasons, she wanted to meet with her heart donor. To accomplish this, she wanted his help. He did just that, but it seems like the dead detective, Siesta, is related to all of this. Since "the detective is already dead," she can't possibly be alive, but her mysterious past will no doubt influence Kimizuka's current reality.
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The characters and the world setting are really interesting, so I liked this novel quite a bit. Each character has its own appeal, making me fond of a number of them. The story and the developments are fun; however, this novel is not a mystery but an SF (science fiction). Personally, I didn't mind this at all, but others may care about this point. Originally, I haven't read many mystery stories, so I didn't really expect much from this novel related to that.

For those interested, I highly recommend this.
Profile Image for Sarul Sakulthong.
227 reviews4 followers
March 29, 2023
ยอดนักสืบตายแล้ว จริงๆนะ!!
<รีวิวนี้มีการสปอยล์อนิเมะตอนที่ 1 เล็กน้อย!!>
ผมเริ่มรู้จักเรื่องนี้จากอนิเมะชื่อเดียวกัน แต่ผมรู้สึกผิดหวังมาก เนื่องจากอนิเมะเริ่มเรื่องมาด้วยการเปิดตัวเซียสต้า โฉมงามผู้เรียกตัวเองว่ายอดนักสืบ ได้ชวนพระเอกไปเป็นผู้ช่วย เพื่อร่วมผจญภัยกำจัดองค์กรชั่วร้ายด้วยกัน ด้วยความที่เคมีของพระเอกกับเซียสต้าเข้ากันสุดๆ หลังจากดูตอนแรกจบผมคาดหวังหนักมากว่าจะได้รับชมการผจญภัยสุดระทึกของ 2 คู่หู แต่ปรากฎว่ากลับเจอความจริงกระแทกหน้าเข้าอย่างจังว่า นางเอกอย่างเซียสต้าตายแล้ว ฮะ!? ไอ้เราก็นึกว่าชื่อเรื่องมันคงปั่นแหละ แล้วคงเฉลยว่าจริงๆคืออะไร แต่แบบ.....ยอดนักสืบ.....ตายแล้ว....จริงๆนะ! แล้วเซียสต้าก็หมดบทไปอย่างนั้นแบบงงๆ แล้วแทนที่ด้วยนางเอกคนใหม่อย่างนางิสะ ผมเลยหมดอารมณ์ดูอนิเมะต่อให้จบ ดรอปมันเลยแล้วกัน

ทว่าหลังจากนั้น ผมไปอ่านเจอหลายๆรีวิวพูดกันว่านิยายดำเนินเรื่องดีกว่าอนิเมะเยอะ ผมเลยให้โอกาสเรื่องนี้อีกสักครั้ง โดยการหยิบนิยายเล่มนี้ขึ้นมาอ่าน (ยอมให้เพราะหลงรักเซียสต้าไปแล้วแหละ) ซึ่งก็เป็นดั่งคำเล่าลือ แม้พล็อตจะไม่ต่างกันกับอนิเมะมาก แต่จังหวะจะโคนในการเล่าเรื่องดีกว่ากันลิบลับ เซียสต้าในนิยายกลายเป็นตัวละครยอดนักสืบปริศนาที่ค่อยๆเฉลยเรื่องราวเกี่ยวกับเธอทีละนิดให้ผู้อ่านได้ค่อยๆรู้จัก แทนที่จะทำการเปิดตัวเปรี้ยงปร้างอลังการแบบในอนิเมะ แถมพอมาเดินเรื่องแบบนี้คนอ่านก็ไม่รู้สึกอคติกับนางิสะด้วยว่ามาแทนที่เซียสต้า แม้ช่วงประมาณ 70% แรกจะเล่าแบบเนือยๆไปบ้าง แต่ก็เข้าใจได้ว่าผู้เขียนกำลังปูพื้นเพื่อนำไปสู่เรื่องราวที่ยิ่งใหญ่อลังการกว่าเดิม รู้สึกได้เลยว่าในอนาคตอีกหลายเล่มข้างหน้ามันจะต้อง Mind blowing แน่ๆ ส่วน 30% สุดท้ายของเล่มบอกเลยว่าวางไม่ลง สนุกแบบสนุกมาก อ่านไปยิ้มไปขนลุกไปแบบรู้ตัวอีกทีก็จบเล่มเสียแล้ว ส่วนจุดแปลกๆของเรื่องนี้คือบอกไม่ค่อยถูกว่ามันอยู่ใน Genre ไหนกันแน่ เหมือนพี่คนเขียนท่านอยากจะเขียนมันทุกแนว ผลที่ออกมาคือนักสืบตายแล้วเลยเป็นนิยายที่แบบ สืบสวนสอบสวนก็อยากเป็น แอคชันก็อยากมี ไซไฟก็ต้องมา โรแมนติกคอมมาดี้ก็ต้องได้ แต่ไม่ได้บอกว่าจุดนี้มันไม่ดีนะ ผมค่อนข้างชอบเลยที่มันเป็นแบบนี้ แต่คนที่เห็นชื่อเรื่องแล้วคาดหวังว่าจะได้อ่านเรื่องราวสอบสวนสืบสวนเข้มข้นประดุจนิยายอกาธา คริสตี หรือเชอล็อค โฮล์มอาจจะต้องผิดหวัง
Profile Image for bijak.
3 reviews1 follower
November 5, 2024
「一流の探偵っていうのは、事件が起きる前に事件を解決しておくものだから」


Despite the name of the series somewhat implying this to be a mystery, it's really not. The series is more along the lines of what would happen if Marvel made a 'mystery' series: lots of quips, lots of action, a massively expanding info-dump driven world-building approach, and then a detective and assistant duo and some of the trappings of a mystery thrown in for flavor. Overall, this plays out much more like a superhero movie (mixed with spy film) than a detective series.

When this is doing what I enjoyed - fun banter between the characters, primarily - I was quite enjoying it. When it was doing what I didn't enjoy - info dumps about secret organizations and the like - I was just waiting to get back to some more silly action and banter.

Overall I had enough fun reading this to continue on with the series, but it is definitely not something you can take too seriously while reading and still enjoy it. For what it's worth, I do think once the whole cast gets assembled later on in the series it more hits its stride, but it never really strays from the formula established in this volume.
Profile Image for Amber Grissom.
45 reviews2 followers
July 2, 2021
I received a digital copy of this via Edelweiss and Yen On, an imprint of Yen Press, for review. I requested this title simply because I was drawn in by the title and the news that an upcoming anime had been announced for it. This light novel had some mild sci-fi elements, with "pseudohumans" and special abilities, that led for an interesting story by Nigozyu. I was surprised by how much I ended up enjoying this story, despite the at times cheesy-ness of the content. With how the Ace Detective Siesta's story is told in this novel, it is interesting, but seems complete. It makes it a little difficult how to anticipate this same title would work for the future books in the series, with the finality of it. This novel could have been stand alone. Regardless, I did enjoy this light novel and the anticipate the next in the series from the ending teaser quotes.
Profile Image for Di.
582 reviews32 followers
November 25, 2023
This one took me a while to get into. I wouldn't say it's a mystery, though you do see our main character involved in a few cases here. It felt more like a low thrill spy story to me with a lot of coincidence thrown in.

I'm glad I picked this up in light novel form instead of the manga because just reading the text you can tell how much fanservice is in the manga and it is not something I enjoy. The main character talks to himself a lot and the way the dialogue is formatted really makes it difficult to tell who is speaking when there is more than two people.

I do have more installments of this series and I wasn't sure I was going to read them with how I was feeling about 50% in, but now that the groundwork seems to be laid, I'm hoping the next one will work out better for me.
Profile Image for Wordsworn.
292 reviews53 followers
July 8, 2022
If I could give this negative stars, I would.

The premise is weak from the start, and the whole story is told in a strange order, which makes it difficult to follow. The main character isn't compelling, and while the female lead seems cool, she's also the "already dead" detective from the title, which makes it hard to even want to get attached to her. The other female lead they add is just there for T&A, she's immediately going on about her kinks and just isn't likeable at all.

There's plenty of good manga out there, and this isn't one of them. My advice: don't waste your time with this mess.
Profile Image for Love.
396 reviews
March 15, 2022
My first light novel series that is not part of an existing franchise.

The concept is interesting. The writing is smooth however I didn't like the characters much they seemed a bit immature to my liking and also there's little mystery cases to solve and more like reading through the characters' narrative. I liked Siesta and hoped to see much of her but unfortunately the detective is already dead.

Almost 3/5, recommended for young adult readers and/or for people not looking for complicated stories but wanting to see the characters going through a generic journey.
Profile Image for Karrie Wagner.
324 reviews11 followers
January 24, 2022
I'm not in love with this series, not really my jam. I found the concept interesting but didn't really vibe with the characters. I read this to get familiar with light novels for my MAC program. Gotta stay hip with the kids.
79 reviews
June 5, 2023
100% straight chuuni with no sarcasm. I would probably have given this 5 stars if I read it 20 years ago, but I'm well passed the age and there's been so many similar works with the same writing style and cliché that it's impossible to take this seriously anymore.
Profile Image for Holly Pick.
44 reviews1 follower
April 11, 2024
Very cute introduction into this story. Maybe a 20-30 minute read? It will be a quick series for sure. Very interested in the detective Siesta and what we’ll get to learn about her throughout the series.
10 reviews2 followers
June 28, 2021
Honestly didn’t expect to enjoy this one as much as I did. Anime is also airing next season so keep an eye out for that!
Profile Image for Kathleen.
3,629 reviews7 followers
May 2, 2022
An odd mishmash of mystery, science fiction, and romantic comedy, but it works!
1 review
August 3, 2022
It’s was short but great the first couple chapters were a little weird but by the end I really enjoyed it. I will definitely be buying the second book. Ps so many hot people
Profile Image for Eternity.
66 reviews
Read
August 30, 2022
So at first, I thought maybe I wasn't going to like it, but I read it this weekend, and it got more interesting, so next weekend I'm going to get the second and third!
31 reviews
November 25, 2022
Fun Adventure

Very well written book. Loved the story line. Concept was pretty cool and the characters were so fun. Can’t wait to read Vol. 2.
Author 14 books37 followers
July 9, 2021
Started reading this series because I watched episode 1 of the anime.

The plot of volume 1 is a little bit shaky. It presents itself in a combination of current day and flashback, and introduces characters with little to no prior buildup, preferring instead to haphazardly explain their role in the story after they get introduced.

Despite that, I still had a great time reading this LN. While the worldbuilding and some of the structure reflects the fact that this is the author's first novel, this novel shines in its character interactions. I got drawn into this series despite its structural flaws because the connections between characters had a genuine emotional impact on me.

By the way, this is NOT a detective novel. While one of the MCs is a detective (Siesta best girl), she's overly competent to the point where there isn't actually a mystery. If you go in with that expectation, you're not going to like this.
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396 reviews41 followers
August 23, 2023
The novel was easier to follow than the anime which put the end of this book at the end of the show, but they probably did that to get 12 episodes but ended up jumping back and forth 3-4 years. But the series did interest me enough to start the books. Another issue was that from the title a lot of people expected a mystery story but is actually multiple genres. The story about the home in the woods with the girl in bed wasn’t in the anime.
This entire review has been hidden because of spoilers.
7 reviews
July 9, 2022
A horrible mess of genres that successfully fails in every single one. I have no qualms with more ambitious story structures but this wasn't a good example of mixing detective with superpowers action and the "Siesta twists" are honestly more hilarious than anything. From what I read of volume 2, it only gets worse.
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