Why do you get scared by horror flicks?

All of them are scary because they represent evil and what it wants to do to us. Add to that the fact that we often do not know how to protect ourselves from the aggression of these things. Who really knows how to fend off a demon or a ghost or an alien, or a monster? A psycho killer will go to extremes few of us will even think of, so that makes him scary to us too.