A powerful demon
The difference is that the Unbreakable franchise (Unbreakable is the third film in the series) takes inspiration from comics of the 70's or lower. However, you could make the case that is similar to the X-men films, or at least some parts of Professor X.I liked it and I'm curious about it. I'm still on the fence about seeing it. The big question (rhetorical) is do you want to see a standalone origin story for the joker?
PS. that sentence reminded me of SPLIT.
The theme I took away is "how would someone like this slip through the cracks?"
"Joker" is its own story. I think that, if Warner Bros. sees sales climb, a sequel will be green lit, so they can continue this M-rated formula, and leading into the Justice League universe kinda like MCU.