What’s a movie that had you completely hooked… until the last 10 minutes ruined everything?

Nothing is worse than being fully invested in a movie, only for the ending to completely drop the ball. Maybe it was a lazy twist, an unresolved plot, or something so ridiculous it made you question why you watched the whole thing.

For me, I Am Legend had me right up until that wildly different ending compared to the book. It felt like they threw out all the buildup for a generic Hollywood conclusion.

Also, The Mist—an incredible, gut-punch ending, but still one that made me sit there in stunned disbelief.

What’s a movie where the ending ruined the whole experience for you?

Edit: Thank you to everyone who commented, now I have a metric ton of films to track down and watch, even if they're bad, I do love twist endings, they help me write better.