I know this is not very original but I finally got round to watching Parasite recently and I thought that the ending for that was great. It kind of has two endings in one... the one that the audience would like to see and then what actually happens. In this sense, it's kind of similar to Greta Gerwig's Little Women, which really plays with the idea of the "marketable" ending versus the ending that best fits the story or the character.

I watched la haine a couple weeks ago it is a french movie about the young people in the suburbs and the ending really left my mouth open for a couple minutes as the movie finished i closed my laptop and went to bathroom and tried to understand what on earth just happened.

And for the worst ending well there are a lot of bad endings but nothing comes to the mind at the moment...

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