In one of my previous blog entries, on storytelling in games, I suggested that the lack of a player's fear of death is one of the main reasons cinematic storytelling cannot work in the gaming medium. I also suggested that games which have used this knowledge as part of their story, rather than trying to ignore it, have been among the most fascinating and successful in the medium's short history.

Pathologic is a game obsessed with death and, more importantly, the consequences of death. It is not the player's demise that is the issue - as in most games, if anything it's a minor frustration. Instead, it is the deaths of the other characters populating the game that will come to weigh so very heavily on your mind.

The story sees you taking control of one of three characters, all healers of sorts (the Bachelor, a trained city doctor; the Haruspex, a shaman; the Devotress, a witch-type), who arrive in a small Russian town which has been overrun by a devastating plague. The game has a time limit of twelve days and on each day, the player is given one vital task to perform, plus a few minor ones that earn rewards if completed.

If the key task is completed, the player takes a step towards discovering the source of the disease. If the player fails on the other hand, someone they know will die. And I'm talking important characters here, not just one of the many identikit civilians lurching around town (more on them later). The death of one of these characters doesn't stop the player from completing the game, but ups the difficulty of days to come and makes completing subsequent tasks that little bit more arduous.

At this point you're probably thinking that if that's the case, why not just reload and start again? If time is limited and videogame time can be reset, then why not do so?

Here's the reason, and it's at the very heart of what makes Pathologic such an incredible experience: this is not a nice game. And I don't mean because the scenario is a bit grim or because characters can be killed off. I mean the actual experience of sitting down in front of your keyboard, of completing each task, of counting down the days still to come until that uncertain end, is horrible.

To call it a game is only true in the sense of a game of manipulation, an almighty tug-of-war between your will to reach the finish line and the game's utter determination to stop you. In medical science, a pathologic fracture describes a bone which has not fractured due to any sudden powerful impact, but rather has been worn down and debilitated over a long period of time until one day it just breaks. In Pathologic, you are that bone.

It is your duty to stay strong and not give into the disease that is gradually sapping your will to stand strong for a moment longer than you can. You will not reload the game because each day in Pathologic's sick little town is long and hard. It is simply more preferable to move on, sticking to the knowledge that there is still a chance of success even if the road will get bumpier, than the mental torture of knowing you will not being able to cross another gruelling day off your countdown.

No recourse is given to making the experience easier for the player than it should be: your moving speed is painfully slow, just as in real life where it always seems to take several minutes longer to reach anywhere on foot than you want it to. If you enter one of the town's diseased areas, your health will rapidly seep away until you treat it with any limited medical supplies you might have. Food is limited and prices skyrocket the moment you buy anything or hesitate long enough for the disease's grip to strengthen.

Meanwhile, the townspeople's reactions to your presence are guided by a simple but beautifully implemented reputation system: do good, which in this place amounts to helping the sick with your vital supplies, and you'll win favour - but then, is that small reward worth it given how incredibly difficult it is to come by even some bandages and a few pills that could be the difference for you later on between life and death? Do bad on the other hand (break into a house, kill etc.) and people will hate you.

But then, this is a town overrun with disease and rationality is no longer an affordable luxury: one day you might wake up and discover that everyone hates you due to a spreading rumour or some misrepresented act you undertook 'for the greater good', only nobody else sees it that way. Not only that, but you won't be able to make progress without occasionally sacrificing what little goodwill you've earned. The game won't force it on you, but you'll quickly realise there's no way around it. Besides, what's the life of one tramp to save the whole town? It's the greater good, right? Wait until no-one's watching, kill him quickly and take what you need. The greater good.

Then at the end of the day, when you are updated on the death count over the past twenty-four hours, even when that number hits the hundreds and you've made vital progress thanks to that item or dissection courtesy of your deceased friend, you won't be able to stop reminding yourself that one of those hundreds had nothing to do with the disease. It was all down to you. The one brought in to make things better.

But if the game is so unremittingly grim, why would anyone willingly persist?

Think back to a time when you were performing a tough task that you didn't want to do and weren't enjoying, but just kept persevering anyway. Remember that voice in the back of your head that whispered "You've come this far! Imagine how proud you'll be if you fight to the end! Can you really live with yourself knowing you've given up?" That's what Pathologic does: it gets in your head. Everything about the game is utterly fascinating, in a very sick way: the architecture of the buildings is broken and diseased, stark yet meaningful.

There are three magnificent, intimidating superstructures (the Abattoir, the Avery and the Polyhedron) that loom over the town yet are inaccessible for much of the game (or even at all, if your character's storyline or actions don't happen to lead them there) but seem central to everything that is going on. You'll long to be allowed through those doors, just to satisfy that curiosity or indulge that niggling sense of terrified awe. But to do that, you'll have to wait and make do with whatever little morsels of information the game throws to the floor for you to gobble up. Then there's the raven-faced executor, who appears as an angel of death outside a character's house whenever a task is failed, speaking to you directly as the player rather than the character, or the mime, whose blank face and knowledge of supernatural information is somehow just as unsettling.

A Brechtian concept of the theatre made real is intertwined all the way through the story, not least in the between-day interludes where you watch a strange performance on stage depicting the day's decisions and events which might well be taking place inside your own head. Or your character's head. As if you know which is which by that point, anymore. Meanwhile, the executor tells you at the beginning of the game that you and your closest associates are the only ones who truly count: they get their own photos and detailed (if unquestionably ugly) character models.

The 'extras' walking around town comprise of fewer than five models, untidily animated and often repeating actions. You'll remind yourself of this when faced with one of those moral crises mentioned previously. But then, aren't they, the regular townsfolk, the ones you're there to save? If you and your associates are the town's bones, keeping the body upright, then they must be the flesh, binding it all together and giving it purpose. For the record, that metaphor was very carefully chosen, but you'll have to play the game to find out why (and when you do and you realise what the game has left sitting under your nose all along, I can guarantee: you will gasp).

In the game's few English-language reviews, it has been pointed out that by any rational standard, Pathologic is technically deficient and even outright broken. And they're right: the visuals are jagged and blocky, as though lifted from a game five years older, coloured in greys and browns and suffused with a thick fog that limits vision to little further than twenty feet. In any other game, this would indeed be a graphical disaster. But in Pathologic? It's seeping with oppressive atmosphere. Meanwhile, if you play the English version of the game, you'll soon discover that the translation work is so bad that many characters' vital exposition is borderline incomprehensible. You'll swear at the broken mechanics, but whether intentional or not, the sense of disorientation they create are ferocious. It's not just the town that's diseased, it's the game itself, adding a whole unexpected layer of depth that would be lost should these 'problems' be 'fixed'.

Pathologic is an experience that disproves everything you thought you knew or believed about videogames. It shows up the expectation that a game simply be 'fun' to be worthwhile as utterly baseless: Pathologic is miserable, psychologically exhausting, graphically dreadful and broken in key areas, yet is more compelling and evocative and astonishing than any other game you're likely to play, an FPS where the first thing you'll do upon finding a gun is trade it in for life-giving supplies.

It is the antithesis of user-friendliness, yet you'll keep on crawling back, suffering through its ordeals in the hope that it throws you some inch of relief. Its writing is abstract, thematically vague and any conclusions you come away with will at the end will have mostly been pieced together by your own sense of desperation to find meaning rather than any concrete evidence. The only way to get through it is to stop trying to play the game - find shortcuts, break the reputation system, 'win' in any conventional sense - and instead let the game play you, move you where it wants to and accept the sadistic whims it exerts. It is the most crushing but brutally fulfilling and complete forty hours you'll spend in front of a PC screen.

While the mainstream games industry continues to emptily justify its claims to be art or to create resonant masterpieces, sitting quietly and forgotten in its darkest shadows is Pathologic, an experience forged in the Russian formalist traditions that gave Brecht to the theatre world and Dostoyevsky to literature. The greatest game you'll never want to play.