When a movie plot twist is done right, it can become an enduring part of the pop-culture bubble for decades and decades, sometimes even becoming independently famous away from the film that it originated from.
The Sixth Sense. Psycho. Fight Club. The Prestige. Mention any of those films and chances are, you'll end up in a discussion about their twists almost immediately, with their shock value, story ramifications and general cleverness making for some satisfying narrative turns that are still entertaining to watch, even after all this time.
But the dangerous thing about plot twists is that - because they're meant to be big surprises that reframe the movie's narrative - fans can often feel like a story has promised them one thing, only for a bizarre and unwarranted twist to come out of nowhere and give them another.
Worse still, some twists don't seem to serve any purpose other than providing a cheap bit of shock value, punishing viewers who've invested their loyalty in a story by plucking an odd reveal or pointless character death out of thin air.
We all love a good twist (who doesn't?) but what we don't love is feeling like our time investment has been wasted.