I didn’t know the future was so … retro. The Computer Space video game, bubble wrap on the sliding door, psychedelic music.
Snape kills Dumbledore.
I only decided to seek out Soylent Green because of the … plot twist; but it turns out that knowing this particular plot twist took quite a bit of wind out of the film’s sails.
With the Harry Potter series, other than knowing about the famous line, I went into it completely blind. The surprise may have been ruined; but it certainly increased the amount of drama for me; because I would tense up every single time Snape and Dumbledore would appear together. When Dumbledore finally died it was almost a relief.