Great fear in me is infused with horror films about maniacs (serial killers). Such a plot is quite real and it becomes frightening. The most dangerous people do not stand out from the crowd, you will never think that this person is capable of terrible deeds. Documentary films tell us that usually even the parents or spouses of murderers do not know about their "secret" life. It's terrible to imagine what our colleagues or a saleswoman from a nearby supermarket are capable of. :) But if you think about this, you can earn paranoia !;)