I don't always read series in order. At least, not with novel series. I usually assume books in a detective series won't spoil previous ones, and most of the time, I'd be right. Reading out of order is something I especially tend to do with older series with many entries, as I often decide to read the most interesting sounding story first and then just make my way through what's available, while with more recent series.. I just happen to start with the first book because it's the only one out at that moment. So it's not really a choice then. I do think it's interesting at times to start somewhere midway, and then slowly learning what the "patterns" of a certain series and writer are as you make your way back into the series, it usually feels more surprising than just reading the books in order. However, occassionally, I do regret reading certain series out of order. Today's book is one of them.
2000 years ago, Hermes, offspring of God, descended upon the planet to convey upon people the Seven Divine Secrets: the day humans would solve all seven of them, step by step, they would be able to reach the realm of God. It would take nearly two thousand years before humans would finally solve the first secret, teaching them the secret of transmutation, or alchemy, giving mankind the power to transmutate mattter at an elemental level. Since then, there have always been no more, no less than seven alchemists on the planet, always one dying before a new one arises. These alchemists are the only ones to have mastered the lowest level of the Divine Secrets, so they are also the only ones capable of figuring out the next step on the pyramid of the Seven Divine Secrets. Decades have passed since Magnus, the first alchemist, lived and it's in recent years that the alchemist Ferdinand III managed to solve the secret of Aether materalization and the creation of Aether-batteries has led to an energy revolution and the manufacturing of Aether-powered vehicles and other machines. Alchemists are seen as the most powerful people on the world, and therefore also considered a political and military force. Many of them are employed by states like Astarte or Bahl, but Ferdinand III is one of the exceptions: he is employed as a private consultant by the Mercury Company, a private enterprise from Astarte that has made a fortune thanks to Ferdinand III's materialization of Aether, His research has made the Mercury Company a force to be reckoned with, even by the government of the Kingdom of Astarte. Mercury Company has grown so powerful, they have their own city: Trismegistos is a Aether-powered city that floats above a lake and is a full-blown city, with at its center Mercury Company's HQ and deep within the basement of that building lies Ferdinand III's laboratory.
Emilia Schwartzdelphine was once a promising (male) cadet of the Academy, but circumstances had made him an outcast upon graduation, and he was posted far away from the capital. His direct superior wants to have him back however because he knows Emilia's capabilities, and he arranges for a task for Emilia, that upon completion, will allow him to return to the capital for good. Emilia is act as an observer to Theresa Paracelsus, head of the special military unit Alkahest: the foul-mouthed, and somewhat lazy Theresa is the sole State Alchemist of Astarte, but a lot of the other divisions in the army don't like the idea of alchemy, so Emilia's boss wants to see if he can find any excuse to get Theresa fired and Alkahest disbanded. Theresa has been invited by the Mercury Company to come to Trismegistos for a few days for a history-making event: Ferdinand III has succeeded in solving the next Divine Secret, the secret of the soul, and will demonstrate this in Trismegistos, with the State Alchemist Theresa as a special guest. Emilia will accompany Theresa to Trismesgistos, keeping an eye on her during their visit. Theresa and Emilia arrive one day before the event in Trismegistos, and meet Ferdinand III in his highly secured basement lab, where he exchanges the usual compliments with Theresa and explains he has indeed succeeded in solving the secret behind the transmutation and creation of souls. His assistant Alraune is actually a homunculus, Ferdinand III's first success, and tomorrow, he will breathe life into a brand new dummy made especially for the presentation in front of everyone. They all retreat that evening to prepare for the event tomorrow, but an alarm wakes up everyone in the night: something is going on in the Ferdinand III's lab. But getting inside isn't easy: three steel doors block the corridor leading to the basement, the first two requiring the hand palms of key persons in Mercury Company, the final door the hand of Ferdinand III himself (meaning it always requires a combination of both Ferdinand and a Mercury Company executive to get inside the lab). When they finally manage to get inside, they find a horrible scene in the lab: Ferdinand III has been impaled on the wall with a zweihander sword made of gold, and Alraune too has been killed. They soon realize this is utterly impossible: not only is there no way for any outside to get in or outside the highly secured lab, but who could ever beat an alchemist in a fight, a person who could change anything around them into a weapon to fight their assailant? Only... an alchemist could. Theresa is quickly fingered as the culprit, as she's the only one who could just transmutate her way through all the security measures, but Emilia doesn't believe she's the killer, and he buys the two of them some time to solve the impossible murder on Ferdinand III before they'll be executed as the killers in Konno Tenryuu's Renkinjutsushi no Misshitsu (2020), which also has the English title Alchemist in Locked Room on the cover.I read the second book in this series, Renkinjutsushi no Shoushitsu or Alchemist in Mercury Tower last year, which I enjoyed a lot as a fantasy mystery story with a unique locked room mystery, even if the depiction of alchemy in this series was a bit odd as it came straight out of Fullmetal Alchemist. Which is of course a great series, but the way alchemy is depicted there is very specific and not in any way like a classic depiction of alchemy, while Renkinjutsushi no Misshitsu seems to pretend like it's the default way to show alchemy, assuming every reader will think it's natural to think alchemy is conducted by placing hands on the object you want to transmutate and light effects and everything appearing. Renkinjutsushi no Misshitsu and its sequel are obviously written in a post-Fullmetal Alchemist world and if you don't know FMA, I suppose the alchemy shown here is utterly baffling, but on the other hand, even knowing FMA I think it's really weird to assume this is a normal way to show alchemy. Anyway, I did mention in my review of the sequel that " I have a feeling that wasn't really the best way now, as this second book does spoil a few details of the first book I think, and in other regards it seems to skip over things that are probably explained in more detail in the first book." I wasn't completely right in that regard, as some things that seemed to be skipped over weren't explained in this first book, but just explained a bit too swiftly in the second, but I was certainly right in saying that the second book did spoil enough about the first book to make me realize what had happened in the locked lab murder right away, so I do recommend other people to read these books in order.
Unlike Renkinjutsushi no Shoushitsu, the first book focuses on one single crime scene, making this a fairly small story. Ferdinand III (and Alraune) were found killed inside the triple-locked underground lab: three steel doors seperate the lab from the rest of Mercury Company's HQ and not one single person can open all three doors by themselves, as while only MC executives can open the first two doors (and there are guards there too!), the last door can only be opened by Ferdinand III himself. Yet the logs show nobody else entered these doors from the moment he was last seen alive until the murder and the alarms inside the lab suddenly went off. The lab itself has no other exits large enough for a person to pass through. Meanwhile, Ferdinand III himself was impaled on the wall by a gigantic zweihander made of gold, which adds to the mystery: who could defeat an alchemist, who can just transmutate anything in his environment into a weapon to fight off any attackers, and why was he killed with a weapon made of gold? It's no wonder the police (with some pressure of the military) suspect Thereasa is the murderer: there are only seven alchemists on the world, and she is the only one near the scene of the crime that night. She would be the only one who could just use alchemy to transmutate holes in the walls to break into the lab (and put them back up), and transmutate a weapon of gold: while transformers are capable of doing low-level alchemy by transforming the shape of objects, only alchemists can conduct elemental transmutation, like creating a weapon of gold. Of course, Emilia doesn't believe Theresa did it, so Theresa and he (and the reader) have to figure out how anyone could've penetrated the triple-locked room and killed Ferdinand without the use of alchemy, despite the existence of alchemy.
In a way, that last line is exactly what makes this book a familiar locked room scenario, one even people who aren't used to seeing fantasy elements in fair play mystery can get used to. For how often have you not read a locked room mystery, which is actually not really a locked room mystery, because there is one suspect who could've done it, but for plot-reasons we are told they are not the killer, for example, because they're the protagonist? One of Carter Dickson (John Dickson Carr)'s most beloved locked room mysteries is exactly like that and Renkinjutsushi no Misshitsu follows the same pattern: it's only really a locked room mystery if you believe one character isn't the killer, even though theoretically only they had the opportunity.
Of course, it would be a bit disappointing to have a mystery novel set in a world with alchemy, transmutation and transformation and not have the solution involve any of that, so yes, the solution to the grand mystery does feature those elements, but alchemy is definitely not used as a cheat here: both transmutation and transformation have specific limitations which are explained and explored in this novel, with both Theresa and Emilia theorizing about what could, and what could not have been archieved with either of those techniques. I do like the idea that the solution is actually lying in a completely different direction than you are probably likely to think off first, and while the answer does utilize alchemy, it is used in a way that isn't just "they made an opening into the lab and then sealed it again," requiring much more creativity from the reader if they want to solve the mystery themselves. I think the misdirection here works, up to an extent: it didn't help that the sequel did spoil a lot of the solution already, but I also think that that ultimately, the book shows off too little of the characters who appear in the story, so quite early on, you already have an idea of who'll be important and not, and because of the limited number of focused puzzle pieces, it becomes fairly simple to arrive at the solution. I like the solution to how the murderer managed to penetrate the locked room, kill the alchemist, and get away a lot in concept, and I do think there are really clever clues and ideas in terms of motive too, but it's told a bit too swiftly, meaning some elements feel a bit underutilized.
And having read the sequel, I did feel the latter was superior in basically all aspects, as it managed to show more interesting aspects of the outside world, while also presenting a trickeier mystery plot, with more false solutions and things like that. Renkinjutsushi no Misshitsu is a promosing first book in the series, introducing the concept of alchemy and using that concept in a fairly interesting way for the locked room mystery in that novel, but it's noticable that the sequel really builds on every aspect of the first novel and manages to improve on them, sometimes in very minor ways, sometimes in more significant ways. So in that sense, reading them in order is perhaps also more fair to Renkinjutsushi no Misshitsu, because it does show growth in the series.
Like the second novel, Renkinjutsushi no Misshitsu is an entertaining locked room mystery that manages to present a fair play mystery in a world where alchemy exists, and it uses the concept of alchemy to challenge the reader with a puzzle that wouldn't be possible otherwise. It's not as cleverly plotted as the sequel, and here and there you might feel the scope of the book is a bit too limited, but overall I think it's a fun read, though I have to repeat myself and say you should read them in order. I for one hope a third novel will be released to see how things will develop even further!