Much of it has, some of it can't (within the realm of human knowledge, but let's leave aliens and immortality for the moment), but could unrealistic but possible things like mass rape and torture in a 1st world nation happen?

Could there be snuff films in your neighbor's basement? Could there be gatherings of Snuff Orgies? Now and then the news reports on smuggling rings being found out and someone showing up dead, but how many don't get caught or even noticed? Could we all be just steps away from a genocide that leads to even bloodier backlash? And by the end find that more horrible atrocities have been committed both recently and throughout history than anyone has known?

I'm not speaking on if such things are moral, they are obviously evil. If you're evil and will do such given the chance, that is your choice but it is evil. No, my only point today is that such people do exist and human nature doesn't limit us to trustworthiness, in fact it usually pullls us the opposite direction.

How susceptible to becoming a monster is the average person, or even an amazing individual?