Edit: PostScript, I found a good article.
https://www.flickeringmyth.com/2020/01/its-chinatown-jake-the-joys-of-the-unhappy-ending/
Edit: PostScript, I found a good article.
https://www.flickeringmyth.com/2020/01/its-chinatown-jake-the-joys-of-the-unhappy-ending/
Vanishing Point
You just reminded me of the vanishing, which is also a fucked up movie OP would like.
Just make sure to watch the original, not the Hollywood remake, which gives it a happy ending.