Yes, BK, it's Twosday, not Whensday--and this must be Belgium.
I must admit that I am usually taken aback by plot twists, if they are not horribly telegraphed. Joe and I watch a lot of B sf and horror movies these days, and sometimes the twists are as simple to guess as "he must be the real villain, why else would John DeLancy take that part", or "they keep showing a close-up of that girl for no reason".
But the major ones like The Sixth Sense and The Others--I hadn't a clew.
Since we don't see movies till they come to cable, I knew about the twist in The Crying Game, but I kept it from Joe, and he was bowled over.
By the way (btw in Internet Lingo) I was very impressed by how the twist in that film was used to do more than just shock the audience. In the first part of the film, we see Stephen Rea being forced to see the British soldier as a human being rather than as The Enemy or The Other (as his cohorts do), and we all empathize with him. The same process occurs in the second part of the film--he and the audience fall for Davidson (except you smarty-pants who figured it out in advance), and when the twist comes you can't simply dismiss her as "one of them", because an emotional attachment has developed.
I saw Sweeney Todd in previews, and the Beggar Woman twist was a total shock. Hey, "if you get it... good, you got it!" was a shock to me and most of the audience that night.
I've always wondered what it must have been like for the first readers of Dr. Jekyll and Mr. Hyde when they came to the "twist" that Jekyll and Hyde were the same person. Oops! Sorry for the spoilers. Hope that doesn't ruin it for anyone.