(and I am not sorry for this pun)
"Tokyo Dark" is defined as point-and-click adventure/visual novel mixture, but I don't think it is a very strong game in either category.
It isn't really point-and-click adventure, even if protagonist can move left and right within the scene and click on some items. Traditional point-and-click adventures let me to wander around several available locations with inventory full of strange items (picked by clicking on everything in environment, often with a funny comment), talk to various NPCs even after they start to loop their speech, and think of different (il)logical ways to use collected items to progress, occasionally solving pretty obtuse puzzles. In "Tokyo Dark" the progression is linear scene-to-scene (with one pseudo-branching investigation 'choice'), the hotspots for interactions are very few, NPCs turn silent once their initial dialogue runs out, and very few collected items are just pegs for the story progress.
As little as I know about visual novels, I don't think the game is particularity strong there either, as there is very little involvement with other characters except Raina, and most of situations have very straightforward, non-conflicting solutions. There are some branching choices, but even in Telltale games there is more tension and involvement with them. There are three not-case-related characters whose fate you can affect, but it is a matter of a couple of lines and one very straightforward advice. I don't think it creates much involvement at the end.
Where this mix works is in the game atmosphere. In a usual visual novel the environment is nothing more than a backdrop for character sprites, but here even protagonist's small freedom to wander left and right within the scene adds greatly to the game and creates the illusion of bigger world. The good design choice is to make hotspots visible and interactable only if the protagonist comes closer, adding some tension and sense of discovery to the whole process even if there isn't that much to discover and nothing actually kills you. The story itself isn't badly written either – nothing to tear up about, just normal; in addition, the walking and clicking segments between dialogues help to space the story pieces. The mystery unfolds in a decent way, the art is not ugly or too saccharine, and the setting-building part is well-done – much done with little – maybe this is why the rather abrupt ending(s), underused mechanics and linear structure(s) of "Tokyo Dark" give, in general, the sense of a letdown.
The launch trailer creates the better impression than the game turned out to be for me: it is frantic, tense, intriguing, fast-paced and dynamic. But 'Explore Tokyo' is a linear sequence of scenes – not bad scenes, but without much to do other than to solve some extremely simplistic 'puzzles' and make one or two ending-influencing choices. "Solve the case" doesn't require any thinking, it just happens. 'Chose your path' is based on few key choices and gives you one of the 10 endings (+ true ending on new game plus), and, unless you intentionally go for nervous wreck state by ignoring multiple options to restore mental stability, 'Enter the Dark' is also going to happen in one way or another. All interesting actions seen in the trailer – such as picking a lock, sitting-in-the-office-seemingly-working-the-case, threatening the sleazy man with bodily harm – happen only once. The game itself is rather short, which might be a benefit because you'd have to replay it at least once if you want to have full scope of the story.
The mask, featured prominently in the trailer, is a major gameplay disappointment. It is certainly a very important part of the story, but from the trailer I imagined that using it would be our choice, that we will be able to influence the story more, to uncover more if we risked using the mask to look at ghosts and events hidden from mundane view, even if for the costs of our sanity. It was not the case in the game, and the mask is just a plot prop.
Speaking of sanity, "Tokyo Dark" has a pseudo-RPG system of four stats: Sanity, Professionalism, Investigation and Neurosis – S.P.I.N. (hence the pun I still don't regret). Such system isn't revolutionary by itself: a lot of interactive fiction and visual novels use some kind of inner stat/flags system to track progress and derive the ending, and some of them make such system visible in one way or another. In this game it is available all the time, shows direct values without any frills, and some NPCs even call direct attention to the system, giving it a sense of importance.
The names for stats fit well: you are playing as a police detective, investigating your missing partner, which very soon turns out to be supernatural affair in the world where paranormal isn't a common state of things. But while every stat supposed to have some effect on either the gameplay or the story, I am finding them underutilized.
Neurosis is, probably, the saddest case. In-game it is gained if you (as a player) repeatedly click on the random items, try to talk to NPCs after the conversation is logically concluded and repeat the same actions; it is a good in-world explanation and deterrence for out-of-world click spamming. The game effects of high Neurosis is less effective restoration of Sanity (and low Sanity, in turn, leads to hallucination, breakdown and terrible endings) so, theoretically, the player has to plan their clicking and dialogue actions carefully to keep Neurosis as low as possible.
Gameplay-wise it isn't that important, though. Conversations are quite brief and bare, with few options, and, past the first chapter, most NPCs become inactive or vanish after their conversation is concluded so there is little opportunity to gain Neurosis this way. Interactable items are few and far between (and they become non-interactive once their purpose in the scene is fulfilled as well), while repeating clicking on plain environment doesn't seem to give any Neurosis. Aside of a couple of optional actions (such as to view a photograph found in sleazy man's hideout) I don't recall ever getting significant Neurosis from anything that isn't a story-mandated situation. More than that, there are several opportunities to restore Sanity that are also restoring Neurosis, so it takes purposeful decision not to heal it for breakdown ending.
Investigation allows you to notice more hotspots and items to interact with, which in turn gives more information about what is going on. You gain Investigation by being curious about things when you encounter them for the first time which means clicking on options available for some of items to look, listen, notice and so on, to gain a bit of Investigation; this gain is small and it is mostly a harmless action. The bulk of Investigation is obtained for the progress of the story (unless character makes too many rash decisions and gets premature ending(s)). Even with pretty average Investigation my progression didn't look to be impeded by the lack of extra details. In another good design choice, half of the options to restore Sanity will also diminish Investigation (as the pills muddle your wits and sedate you), so in this game Investigation is not only a measure of progress but also stands for perception and mental acuteness.
Sanity is sanity: it is pretty much what you expect from the Call of Cthulhu sanity. Low Sanity is supposed to lead to hallucinations, then breakdown, then the bad ending. You unavoidably lose a lot of Sanity in the course of the story, but there are plenty of options to mostly restore it; some of these options don't affect Investigation and also cure Neurosis.
The forth stat, Professionalism, is the most interesting. PC is the police detective and this stat grows when the character acts in a professional manner: orderly, by-the-book, law-abiding, polite, educated, competent, rational, composed and at least slightly emotionally detached. Fast, direct, immediate options, 'Dirty Harry'- or maverick cop-style actions – such as shooting the lock off instead of looking for superintendent with a key, intimidating a man with bodily harm instead of collecting information and using it as a leverage against him, or taking a hostage for immediate gain instead of doing what is expected of you – lowers Professionalism. In-game high value of this stat is supposed to gain you more respect from the others, while low Professionalism is supposed to give you less legal but faster and dirtier options, such as break and entry into forbidden places. As with Neurosis I don't think it significantly affects gameplay or the story progression aside of some dialogue changes and getting different endings after the point of no return.
I am finding it very interesting, this stat and how it played: low Professionalism gives you more blunt, impulsive, fast, underhanded and, eccentrically, more self-reliant, less socially-dependent options, while high Professionalism acts not only as a social skill, not only as a measure of status, but also as a measure of composure and self-control, of the willingness to keep faces, to keep the noise down, to be detached, to be risk-averse, to progress slower, to keep cool head, to be methodical. The whole stat also doubles as Chaos/Law alignment line.
In the fantasy such naming won't work (professional cutpurse is not law-abiding, professional bard is not cool-headed), but in modern setting, especially with limited focus on investigation process, 'professionalism' invokes a certain set of characteristics, that kind of demeanor we get from competent customer services, layers, doctors, bureaucrats, police detectives and so on: proper communication, reliability, competence, calmness, certain set of ethics, composure, emotional detachment, structure, following rules, politeness and so on. I am finding this to be a another good design solution, terse and fitting to the purpose of the game.
All and all, if the game was more complex, if more difficult choices were to be made, more situations present to leverage one risk against another gain, more things to investigate, the S.P.I.N. could have been a good system to use. As of now it looks more like ornament than actual system to the point that one of the endings is completely irrelevant to it.
Supernatural in the setting of the game is what I call 'modern esoterica' – the modern mundane world, where the supernatural is not ever, ever fully reachable or explainable, but even the merest indifferent touch of it brings drastic consequences to few so affected. Dark in 'Tokyo Dark" is always remains just out of direct reach or understanding, and mythology of it seems to be something else than traditional mythological underworld. It gives me Void vibe from Dishonored, and Ink vibe from 'Van Helsing's Adventures', and some of creepypasta and SCP Foundation vibes if I am to parallel it to anything. Dark is an interesting thing, as it is not actively malicious and probably doesn't have any of own will or personality at all – not more character and identity than the sea has or the sky has. It doesn't create monsters to stop you, and while several NPCs in the game are clearly somehow connected to it, they aren't acting on its behalf or by its will. By all scarce information it is more the supernatural catastrophe in a making, WH 40K primordial Warp reacting to a congregated mass of turbulent human lives and desires, with some people (?) learning to carefully, delicately use it for their own means, while some are engulfed into it due to trauma. All and all, especially in a way the game unfolds, it is a decent setup which, hopefully, leaves the setting less oversaturated with various magic and monsters than World of Darkness or urban fantasy do, and without overused personality than Eldritch Things CoC world has.
Incoming console re-release, Tokyo Dark: Remembrance, according to statement "completes the mysteries left by the original, bringing a Director’s Cut of this masterpiece", so maybe the game was just rushed for its Steam release. It would be pity if PC version won't be updated.
