The following post is not for the squeamish, it's not gory visually, but there are certain concepts which, whilst not requiring a trigger warning (I don't think) deal with some of the less pleasant aspects of human behaviour.
Clive Barker's Hellraiser series has a lot of appeal to me, not the kinky aspects of it, that's usually way beyond my comfort zone (but that's what horror should be about of course), but because of the simplicity and complexity of it's "hook" (no pun intended), LeMarchand's Box, the Rubik's Cube from Hell itself.... The Lament Configuration.

As any good Hellraiser fan knows, the Lament Configuration appears to be a small, beautifully intricate puzzle box, an almost irresistible toy to play with, to try and solve, it's all but challenging you to open it to see what's inside....
( But this box makes Pandora's Box look like a lunchbox )