Note: This article contains major spoilers for Scanner Sombre.

A little way into Scanner Sombre, I swam out into a chest-high pool, and my splashing caused something in the cave to respond with a banshee-like wail. I found the source of the noise in the corner of the chamber: it was some coloured mist in the shape of a human. Once I got within seeing-distance of it, it came hurtling towards me and killed me in seconds. At that moment, I thought I knew what kind of game Scanner Sombre was going to be. It was going to be one of those disempowerment horrors where I'd grip my controller, sweaty-palmed, dodging and dashing my way around ghouls. But it wasn't. Soon I was drifting down a tranquil river to some prog rock, and I barely saw another one of those monsters again.

Introversion Software are known for their highly formal simulators like DEFCON, Uplink, and Prison Architect. They're laser-focused, open-ended strategy sims which have you dehumanising other people by taking control of them, their possessions, or their fate through synthetic systems. Scanner Sombre isn't that. Your window into its world involves no bird's eye views or computer interfaces; only a digital spray can. There is no one to dehumanise as it's a mostly solitary affair, and it doesn't have you mastering complex systems; it has you exploring. Scanner Sombre beckons you on through a pitch-black cave, one that you can only see the walls and floors of by shooting coloured dots onto them. It's a cross between The Unfinished Swan and Radiohead's House of Cards video, and true to the experience of hiking through a cavern, Scanner Sombre is a half-and-half blend of creepy and beautiful.

On your first playthrough, you may be on your guard, waiting until you hit the trigger which morphs the experience into a full-blown horror, but Scanner only adopts horror techniques up to the point of setting the foreboding, uncomfortable atmosphere of a cave. Having you chased around by demons or axe murderers would drown out its more understated discomfort and would also sully the majesty of the setting. In this initial foray into 3D first-person games, Introversion is not only devising a way to make a 3D environment without all the texturing that usually requires but also inviting you to indulge in that quality 3D graphics have where it feels like you could reach out and touch them.

You must meticulously pore over the walkways, ledges, streams, and crevices of the cave, charting them with the scanner. The device is like a torch but with less volatile illumination. It's all pure cane eye candy, not just because of the rainbow pointillism of the light gun, but also because you get to see solid shapes form miraculously out of the void. Then, after you've spent a while drawing in all the rocks and gates and stalagmites, you can look out on them knowing that their very visibility is a graphical representation of your work. Painting with the LIDAR creates a measuring stick for your progress. There are various moments in your climb when you can stop, look back, and see your rainbow sculpture trailing behind you. The longer that trail, the more scanning you know you've done. At the end, Introversion award you with a lavish sweep of the camera across the entirety of your cave map, and about two-thirds of the way in, they give you another treat for your efforts: an alternative way to view the LIDAR dots.

A late-game headset upgrade colour codes materials, distinguishing walls from stairs from handrails and so on, which opens the levels up to include more complex mazes without them getting stupidly confusing to look at. The upgrade does, however, use a gaudy colour palette of matrix green, sky blue, burnt orange, and white. Scanner also breaks its own artistic rules around the time you get this upgrade by realistically rendering control panels in the cave instead of drawing them out with dots like every other object. It does this so that you can tell that these interfaces are mission-critical, but anything that breaks its signature dot matrix isn't worth including. These scuffs and scratches aside, what the game does with the LIDAR is arrestingly gorgeous, and the reasons why you need that device in the first place reveal why Scanner Sombre is so unsettling.

Until you highlight the rock floors beneath you, you feel like your next step could send you plummeting off the edge of a cliff because all you see in front of you is hungry darkness. Come to mention it, you could be stepping off the edge of a cliff. Sheer drops and spirit-infested waters lie in wait for anyone not doing their prep work. Like a real explorer, you always need to watch your step, only moving once you have a clear picture of the path ahead. And even once you know the shape of these chambers and tunnels, a fear of the unknown remains because you only see a reverberation of the setting; the detail, texture, and colour of it remain beyond your perception. You can hear echoes from the cave piercing the blackness: There are the sounds of water dripping from the ceiling and gravel crunching under your feet, but this combination of abstracted visuals and realistic audio only makes it more uncanny. The echoes of the cave and LIDAR line up with the nature of the ghosts, as these souls are echoes of people long gone.

Because the scanner provides no photo imaging, it feels like an authentic piece of scientific technology. Scientists often make discoveries about the world not by directly observing what they hope to find, but by witnessing the impression of it, and likewise, you can never see the cave, only the imprint of the cave. It's also hinted that the protagonist's exploration of the cavern is an academic one: they make various anthropological comments about an ancient civilisation who used it as a place of worship. The only things that the protagonist can't explain rationally are the traces of the dead which are visible through their headset.

The game does not attempt to hide the suggestion that these afterimages of people are the ghosts of those who died excruciating deaths in the cave and is similarly nonchalant when it later tells us that the protagonist is living in a time loop where they make this same hike recursively. A part of me wants to scold Scanner Sombre for not making more out of the latter twist, but at the same time, there are already a few sci-fi stories which make use of time loops. By playing it cool with this surprise, the game doesn't try to force genre-savvy players to be wowed by concepts they're already familiar with. The letdown is that while Introversion's confident handling of the "repeating time" plot point makes them look like they know what they're doing, I've seen a lot of players come away from Scanner disgruntled, calling its ending amateurish.

The complaint is that the game's prestige is divulging that you were dead all along, although this isn't what I thought the ending was trying to draw attention to. Once I got the text popup about halfway through that told me the protagonist was living in their own subterranean Groundhog Day, I thought it was implicit that they were dead or trapped in a computerised afterlife. The ending mentions the character's death in symbols of one syllable, but I assumed that this was meant to be a confirmation of the protagonist's death and a reflection on what their death means to them rather than a Shyamalanian "gotcha". Either way, the ending is mismanaged. The character bares his heart to us, explaining the agony of being separated from his family who visit the cave to pay tribute to him, but personal tragedies only work in scripts when there is a person for those tragedies to happen to. The protagonist up to this point has just been a chronicler for the history of the caves; the popups in the game were not their diary. So who is this person that has had their soul torn in two by losing their wife and kids? Getting to the lake where we find their family also involves a slow elevator ride backed by an eruption of heavenly music, but long lift rides in games never scream "deliverance".

Being as charitable as I can, Introversion does try to direct a different sort of ending for the "person crawling through a cave" genre than others have. Scanner Sombre misdirects you into thinking it may be building to a hopeless horror ending a la The Descent. Then, when you find an exit to the cave, it pretends for a minute that you might see an ending where the protagonist tastes sweet freedom like in As Above, So Below. You get neither of these: What Scanner Sombre sees fit for its conclusion is a tear-jerker ending which is refreshing, although the game prevents it sinking in with an epilogue in which it reveals you're one of the screaming killers from the pools of water. As an attempt at existential horror, it's not as disturbing as knowing this character is forever separated from their family, stuck wandering the cave for all eternity. The note the game should have ended on exists before the epilogue.

Still, the news of your demise does wrap up some of the game's mysteries with a nice bow. Those glitchy spirits your headset picked up on may have been the protagonist dying on previous runs through the tunnels; the man-as-monster coda would appear to be a clue to that. The former lives of the player character may also account for the existence of all those scanners in the caves with upgrades on them: previous versions of the protagonist might have dropped them. And we can explain the realistic rendering of the tent at the start of the game and the family at the end in that, unlike the rocky prison in between, these things feel real to the protagonist. These are all smart little easter eggs that are easy to miss, especially if you can't get that dreadful ending out of your head.

What we may be seeing in Scanner Sombre are teething pains from Introversion Software as they grow into exploration-driven narratives. If you've never written a substantial story for your game before, the first one you pen is probably going to be bad. For most studios, not this bad, but you if you remember how green Introversion are at this, you might start to understand why parts of Scanner Sombre are cliched or tone deaf. Having said that, Introversion also lack any history in 3D exploration gameplay and yet use it like seasoned pros here. Not only does Scanner Sombre have an alluring three-dimensional environment, but the way that environment bursts into existence gets the most out of all those dimensional axes. Scanner Sombre teaches us not just to find something magnificent in a setting but also in the unfolding of it. Thanks for reading.