Sleuth is pretty good for its twisty turny plot and knockout ending.
Infinity War had an unexpected ending--even though a lot of the people who went to see it in theaters knew another Avengers film would come out the next year, there was still a sense of "well, I didn't see that coming." (or maybe that's just me)
Same here. I thought it was a great ending that topped off an excellent film.I don't know what I was expecting as an ending but I wasn't expecting the one we got from Three Billboards Outside Ebbing, Missouri [2017]
The Empire strikes back - What? Who's his father?
Bloody hell, Danny, don't give it away.
Deep Blue Sea; the one about the shark with the enhanced brain(?), etc., & there was this guy, whom we were led to believe his end was near, but, instead, the sharks eats Samuel L. Jackson! O.k., might not have been the ending, but definitely did not see that coming!
Though not particularly fantasy, unless you count the alternate history towards the end, I found Once Upon A Time In Hollywood to have a really surprising ending. I went through the whole movie anxious because I was thinking - Oh, no! I know how this story ends for some of these people!
I was pleasantly surprised when the movie proved me wrong, fictional as it was.