I have a collection (Movies with a Twist) and was pondering which one should be #1.
As for the movie I chose - A friend told me I should watch this movie as he thought I would like it because it had a twist to it. Also, he was curious as to how long it would take me to figure it out. I watched this movie with that conversation in the back of my mind, but failed to realize the truth until the damned ring rolled out from under the chair. My immediate thought was "hey that's BS - what about when he..., or when she..., or...". Then the director took me back and showed that he hadn't been dishonest in the telling of the story - I had ASSuMEd too much while watching.
The #1 Movie with a Twist for me is "The Sixth Sense".