Anime that get dark out of nowhere with absolutely no foreshadowing?

Is there anything like this? I know there's a ton of shows that get really dark while at first glance appearing to be cute and fun, but I've never come across anything that gets dark truly out of nowhere. First episode reveals don't count, so I don't want any suggestions where everything is normal until the end of the first episode where they drop the bomb and suddenly everything is revealed. I want anime where it takes at least a few episodes.

But the most important thing is that I want there to be no foreshadowing. With Madoka, I literally saw every single plot twist coming before it happened, because everything was so heavily foreshadowed because I guess they were trying to pull some sort of stunt where people watching casually suddenly have everything click and their minds are blown. This is basically the exact opposite of what I want.

And while Made in Abyss got a fair bit darker than I was expecting, there was plenty of discussion about just how dangerous and unknown stuff was in the first few episodes. They knew generally what they were getting into.

So is there anything that truly has no foreshadowing before it gets dark? Like even if you read the synopsis, the most you're left with is a vague idea that things might not be what they seem? Please don't mention exactly how dark anything gets to keep spoilers to a minimum, as this kind of thread is already inherently pretty spoiler heavy just based on the concept.

And let me say it again, I don't want anything where a reveal happens on the first episode, that doesn't count.

still waiting for any response or support.

192.168.8.1
192.168.100.1
192.168.0.1