Movies I forgot I've seen... until I watched them an entire second time:
You, Me, and DupreeWhen I rewatched these movies, I kept thinking, "I know how this ends... I know how this ends," but I passed it off as the movie being predictable and formulaic. It wasn't until the actual ending -- after two hours of my life had already been stolen -- that I realized I knew the ending because I'd already seen it. It's like when you remember a commercial's jingle but you don't remember the product they're selling. These people didn't do their jobs.
Bridget Jones's Diary: The Edge of Reason
Along Came Polly