Movies you had a mistaken concept of, but don't even know why
One for me was "3:10 To Yuma"
It wasn't the title that did it, but the title seemed fitting after I got this impression.
I swear I remembered reading a blurb that described the movie being partially about time travel, I had the impression of a more mystical "Somewhere in Time" concept, and not a sci-fi "Back to the Future 3" concept. Like someone just stuck in the past and not knowing how it happened, that kind of thing.
Never saw the movie either, obviously, but I did read an actual synopsis years later out of curiosity and realized my error.