Cure
I got to know about this film by scorsese mamey's movie recommendation so It's not flashy it's something that slowly drags you and makes you're subconscious mind get hypnotized but kiyoshi kurosawa really pinched it like chef's kiss
It's like he pointed out Human's chaotic behavior how it's every chaos moments became so normal and the free will concept is frickin amazing important social message tbh.
This was directed in 1997 but it's still a psychological mindcollapse classic.