It's hard to imagine how shocking Psycho's mid-point switcharoo must have been back in 1960, especially when you consider that audiences hadn't even seen a flushing toilet on the big screen at that point in history (we've come a long way, I know). Nowadays, Psycho's unexpected shift - which actually takes place 47 minutes in - seems like old hat: not because it isn't surprising or revolutionary, but because we know it so well. Psycho is the shower scene. In the wake of what is arguably the finest example of a "shocking tone shift," directors who are not Alfred Hitchock have experimented with the idea of changing things up a fair way into their movies with varying degrees of success. Unexpectedly taking your picture into a direction that audiences would have never imagined possible so far into in movie is risky business: there's a chance that movie-goers won't buy it, given how they've spent nearly an hour (give or take) of their time investing in the established tone. Paul Thomas Anderson - director of There Will BeBlood and The Master -nicely categorised these flicks as "gearshift movies." They're the movies that head in what appears to be one direction, stop suddenly, and verge off into places you never expected them to go. It might be that the tone is swapped out for something on the other end of the spectrum entirely, or - in some rare cases - the genre is thrown out and replaced with a new one. Here's 10 movies that - for better or worse - made the decision to confuse, shock, surprise, frustrate, dumbfound or blow us away us with mid-point genre (or tonal) shifts. The big question remains: did the decision pay off? Be warned: major spoilers for all the movies mentioned are contained within.