Alone in the Dark (200

is... it's not underappreciated, it has ~55% on metacritic and that's fair, it's broken, frustrating and unfinished. But it was really forward thinking, it broke a lot of ground.
It had crafting before crafting was a common/mandatory thing and it mostly made sense. If an aerosol can with double sided tape on it can stick to things and then shot to explode... what if you tape a bunch of nails to it... or some glow sticks...
It was an open world survival horror game before The Evil Within 2. It even had cars and driving, it also had side missions that felt natural, like wondering what's in a building you've passed a couple of times or finding an open manhole. There's no leveling up the character or the weapons, you do these things out of curiosity.
It released at the same time as Far Cry 2 and both had fire that propagated, except it was way cooler in AITD because you could burn down more than brush.
No hud or inventory screen or anything like that and the inventory limit was what could fit in Carnby's jacket. Cool and very annoying.
Episodic, you could jump to a later/next chapter if you got stuck and like Alan Wake there was summaries/recaps at the start of every new one.
Physics and deformation. Don't want to find the key? Just break down the door, or set it on fire then kick it to shit when it weakens, if it is a steel door and you have the time then just find something to
smash the lock/handle out of the door frame. Or go for the hinges if they are exposed. It's dynamic deformation that governs this, there's no HP on the door, this means that you can permanently fuck yourself and have to restart the chapter if the door gets smashed in a way so that it is stuck even if you find the key/code.
During the brief moments when the stars align and satan smiles everything comes together the game was fantastic, like being out of weapons and chased by immortal demon-zombies, running into a restroom and spraying the stalls with lighter fluid and setting them on fire, then kicking the stall doors to pieces and using the flaming toilet door to beat the zombies to death because they can only be killed by fire. That happens dynamically and organically, that's what the game was supposed to be, but moments like that might be a combined 30 minutes out of the 10-15 hours that the game takes to complete.
I really like it and I strongly recommend that you don't play it.