It’s no secret, I enjoy a good mystery. Detective fiction is hard to produce, resulting in some very notable misfires, but at the same time when it’s at its best it’s the greatest game between creator and audience there could ever be.
And, one of the greatest staples of mysteries is the Locked Room Murder: a murder committed in a setting where, with the location of the corpse locked from the inside, no culprit should have been able to get in or out of. Locked Room Murder mysteries, done well, always lead to some wonderful, creative, and often sordid solutions.
Without further adieu, The Perfect Insider.
We start with a classically overscored no-context vaguely-philosophical speech. We then follow a rich college girl, Moe Nishinosono, as she visits professor Souhei Saikawa. We’ll learn that the two are student and teacher in, canonically, Architecture, but right now it seems that Professor Saikawa has also been bitten by the philosophy bug, chain smoking as he talks about life’s big questions and the meaning of true freedom, while Moe is just beyond used to this, to the point where you get the impression that she could recite his lines before he does.
Moe moves on to hitting on her professor, but this is interrupted by a request for tech support and a flash to Moe interacting with a weird genius doctorate-holder, Shiki Magata. They go on about the importance of the number seven in the exact pretentious way that would have annoyed Perferator.
As fits pretentiousness, they’re not even correct: “separate the numbers one through ten into two groups and multiply them together. Is it possible for both to be even?” No, they say, because one will be a multiple of seven and the other not. A very cursory bit of math finds that (7×4) and (1x2x3x5x6x8x9x10) are both even. Perhaps they meant equal? I’ll admit that the current streaming subtitles for this show are a little odd. But then you’re just dealing with primes and the only reason three doesn’t get that treatment and seven does is that you’re arbitrarily cutting the system off at ten. I’m going to have to side with the murderer; there’s nothing particularly interesting about seven.
Though, perhaps I should be more specific and say “The murderer from that other show” or “The murderer with the drill”, because Moe shockingly quickly flips from answering math questions to questioning the figure appearing to her via telepresence as to whether or not she really murdered her parents.

Dr. Magata dodges the question, hits Moe in her Saikawa-shaped weak spot, and then Moe is forced to stop reminiscing about this encounter by being jostled back to the present. Later, she talks about it with Saikawa, where we learn that Magata’s official story is that a doll did it, and her official fate was not guilty by reason of insanity (at age 15, having achieved PhD status at 11), resulting in her current habitation in a secret island laboratory to continue her work as a genius programmer.
Moe gets jealous that Saikawa seems to idolize Magata, and because of this arranges for the architecture department retreat to be a campground on the same island where Magata has her not-so-secret secret lab.
The gang of nobodies from the university make their way to camp. On the first night, Moe decides to visit the lab, goading Saikawa into going with her, interspersed with flashbacks to Magata’s past that draw parallels with Moe’s present. While they’re there, there’s an incident with Magata, where after she’s been unresponsive for a while spooky things happen and she seems to escape her ever-sealed room, dressed up in a wedding dress and riding an automatic trolley of sorts to give an ethereal, ghostly impression to her movement.
They then discover that this is a little spookier than a wild escape – Magata is stone dead and, since she’s missing both her arms and both her legs, she must have been murdered in that sealed room.

Now, I will point out that we learn this at the start of episode three. A locked room murder is a very classical setup, but it usually doesn’t take that long to be announced. In some cases, that might have been used for better character development, especially to establish suspects before the killing is revealed, but here it’s just pretentious talk and Moe’s moderately unsuccessful jealous flirting. But the mystery is truly launched, so let’s see how the pacing goes from here.
The lab chief returns in his helicopter, carrying Magata’s younger sister and last living kin. While this is going on, everyone acts pretty calm and rational, planning to call the cops with helicopter wireless while our leads ponder the strange circumstances. However, after an episode of this, said chief is found, still in the helicopter, murdered with a knife to the neck. Seems like a killer is still very much on the loose in the lab.
With the call stopped and the transmitter destroyed, ruining the possibility of simply summoning the cops to solve this case, it’s also time for sleuthing as the lab crew opens up Dr. Magata’s suite to look for clues. The find the area immaculately clean, but also with some mysterious effects including a robot, stuffed animals, and a testament purporting to be from the doctor’s various multiple personalities. All the while, flashbacks continue to tell a story of Magata, before her parents’ murder, seducing her uncle. Said uncle was also the now-murdered lab head, and we even see that the knife used to do him in at least was suspiciously similar to one she gifted him in the past.
Eventually, it’s revealed that a magazine team will be coming over for an interview, promising contact with the outside world. Despite fighting with each other over insane philosophical rambles, they leave the lab, only to spend an episode talking with the folks at camp before deciding to go back to the lab and be snoops.
We move on, actually learning something about our case now that the would-be detectives admit their detective natures, while the flashbacks keep telling the audience things, like how the illicit affair was the grounds for the murder of Dr. Magata’s parents. Magata’s number-obsession, in this case with fifteen (F in Hexidecimal) comes up as a big deal, while the Lab folks worry about covering for the crime, even briefly.
Thus, a mere halfway through the show, we can say we’re investigating in earnest rather than bantering philosophy with a sort of investigation-ish vibe. Not that such a thing stops a weirdo lab member from getting us a little fanservice by getting Moe into a mental imaging pod.

While Saikawa interviews Dr. Magata’s sister, the pod turns out to be the path of plot progress, getting Moe a ghost-in-the-machime meeting with our bizarre murderer and victim, which forces her to confront both what seems to be part of Magata’s world view and the truth of her own parents’ death and the aftermath thereof, including her feelings for Saikawa.
As they consider more about the situation, the two finally come to some conclusions. The first was that no one entered Dr. Magata’s room after she did fifteen years in the past… but there were still two people inside, because she was pregnant from her affair, and raised a child in that hidden lair. This one was, all things considered, blindingly obvious as the audience because we were shown so many affair flashbacks in order to create the assumption that she had been sexually active.
The second revelation is how the culprit escaped the room with the all-seeing cameras, the answer to which was a seven-year countdown baked into the proprietary operating system of the lab that caused, at a precise time, a one-minute duplication where the next minute would be saved over the last. This one is actually pretty clever, and though I’m not sure it was “fair play”, it didn’t have to be.
Thus, Saikawa is able to get a line to the culprit and place a call in order to confront her with the evidence. And who is the culprit? None other than Dr. Magata herself. The corpse was, instead, that of the secret daughter. All this and surprisingly little else comes out when Saikawa and Moe go into the mindspace pods to chat with Magata about this whole situation.

We do at least also get a motive: Dr. Magata raised her daughter to continue a 15-year murder cycle, intending to be killed and replaced, but the daughter broke after the meeting with Moe in the past where they traded barbs and math philosophy, and committed suicide rather than killing her own mother. Thus, Dr. Magata manipulated the situation, escaped her room, offed her former lover, and got away clean. How? She never had a little sister, that was just a persona invented for this moment.
After an admittedly engaging summation and Dr. Magata taking Saikawa on a weird mindspace trip where the two of them click before Magata goes her own way and Moe wakes Saikawa back to reality, we still have one more episode.
Most of that episode is used for two big conversations: Saikawa with the escaped Dr. Magata, where they go over their bizarre philosophies, and Saikawa with Moe, where they go over their bonds and attempt to actually build their chemistry. There’s also a Magata post-script showing some of her time with her daughter, but all’s weird that ends weird.
And weird is certainly how this show started and ended. It’s also, at eleven episodes, quite bloated. The mystery is a very slow burn, waiting until the final summation to solve things you might figure out as soon as they’re introduced. It’s also not a “Fair Play” mystery in any sense, but then it really doesn’t have to be. At least it still essentially holds the the idea that this takes place in a grounded world (albeit with characters whose heads are off in space) so it’s easy to buy the solutions when they’re put on display.
And while I say the show was bloated, it wasn’t exactly boring. There are just a few too many long talks between Saikawa and Moe where Moe acts pointlessly like the jealous girlfriend, or they go over all the things they don’t know.
Speaking of the jealous angle… Moe is supposed to be a polymath super-genius herself. She’s frequently (if only implicitly) compared in parallel with the unrivaled Dr. Magata, and her savant ability to do mental math comes in handy. But most of the time she acts the catty wannabe girlfriend. She’s horribly jealous of Magata from the start, someone that her mark has never actually met and who he professes to admire in a professional sense. She’s horribly jealous of this reporter woman who shows up at the start and end of the show, who is admittedly teasing but who turns out to be Saikawa’s little sister (and a married woman herself, hence the lack of a shared surname). And she blows up at Saikawa over pretty much nothing time and time again.
That said, she’s easier to empathize with than Saikawa himself. Saikawa purports to understand, and be something like mental space alien Dr. Magata, if not quite as far along that path to being some “free” bondless being as she is. He has a flat affect most of the time, and when he’s not solving immediate problems (you’d think he was a programmer, not an architect) he tends to wax long in pretentious talk. For being a morose and disconnected person, he really likes the sound of his own voice when its all about philosophical nonsense.
The basic mystery was very solid: A sordid history, a present that doesn’t seem to add up, and two major solutions (the secret daughter and the lost minute of time) that whether able to be guessed or not are solidly clever. The thing is, this would do for a much shorter mystery. When you get down to it, we need to get to know our leads, discover the bodies, and then identify where the extra person in the room came from and how someone left without being observed. That’s essentially it. You could get some mileage if you had the characters actually dig into Magata’s life and programming work and find solid evidence of her secrets in stages… but even that, put into the format of an anime, should probably top out at four or five episodes.
For as much over that count as The Perfect Insider is, it wears its weight well… but there is still a lot of fat to trim. Combine that with the characters being not particularly connectable, and you have the recipe for a mystery that plays as mediocre but that could have been so much more. I’m open to the idea that the novel is good, even great, but it didn’t make the transition to screen very well. I think what it’s missing is the “Watson”, the character who stands for the audience, who we connect to, and whose speed of deduction we follow. I guess that’s supposed to be Moe, but she’s both an exceptional person and an exceptional mood swinger with a grudge, so she doesn’t really serve as that surrogate very well.
All the same, I’ve certainly seen worse mysteries, and considering only the time to watch, it’s entertaining enough. Further, for a grounded murder mystery that didn’t really have to look like anything, they put a lot of work into it having a visual style. Most of this takes place in a quite sterile computer lab, but all the same many scenes have some great heavy atmosphere.
On reflection, perhaps this is being too kind, but the core of the mystery is so nice and the problems so ultimately non-fatal that I’m going to go ahead and give The Perfect Insider a B-, rather than the C or C+ that I was angling for at first. If you like mysteries, this is one it won’t hurt to check out.