Wow.
Well worth a watch regarding how quickly a sense of power or hopelessness can overcome a seemingly 'average' person.
It only begs more questions due to the multitude of police incidents we're bombarded with today.
The movie is on On-Demand.
https://www.youtube.com/v/3XN2X72jrFk?
Some extra reading regarding the experiment.
http://www.prisonexp.org/
I have been through a mental hell like this. I worked for a Narcissist, sociopathic person right here in good old Jacksonville, Florida. I find it so sad that another human would treat people like they did in this Stanford Prison Experiment or what my ex-boss did for control and to act like a God towards me.