The Area X series (Southern Reach Trilogy) is fucked up!
Ok let me give you a couple reasons if you haven't read it
There's this place, and it seems to be growing that has a weird effect on reality and the longer you stay there the stronger the effect. It centers around a lighthouse in a rural area. The government runs experiments but it's hush hush and nobody knows anything about it. BTW it's getting bigger.
People that leave the area x, might be doppelganger or so changed, it's the same to outside observation.
It's seriously a really good stuff and absolutely fucked up
Not sure if I'd call Area X fucked up but if you liked it definitely take a look at Borne (same author). It mixes the weirdness of area x with bioengineering and much more relatable characters.
did you read the second book? Control goes into that storage room and he realizes that there isn't a storage room there and then he realizes its the scientist is in in the wall and maybe its the doppelganger hiding there and its trying to close the room on him essentially eating him! That part is seriously fucked up. And then WTF happens to Control when he gets to the bottom of the lighthouse stairs? My wife thinks he turns into one of the white rabbits.
Yeah the second book was probably more disturbing, then the third went a bit off the rails. I should probably reread them at some point. I don't remember what happened to Control but the Psychologist's ending was pretty disturbing too.