There is nothing lower than a third-act plot twist. I’m not saying they don’t work from time to time (obviously they do) but putting in an “aha!…didn’t see that one coming!” turnaround is the most tedious dramatic device imaginable. Because everyone uses them, and it’s gotten to the point that we know some kind of third-act twist is coming. If they weren’t so prolific it might be interesting to use one occasionally, but they’ve become an absolute requirement. And that has made them deadly.