The Stanford Prison Experiment was termed as a “psychological study of prison life”. Over 75 folks were invited to apply for this social psychology study funded by the US Office of Naval Research and Sanford University. But this is how it all went 'down'.

As many as 25 mentally and physically sound candidates, who were paid $15 per day, were chosen for this project which involved them staying in a simulated prison environment and the dice started rolling on August 14, 1971. Just like in the real world, those candidates who were given the role of a prisoner to play, were arrested, asked to wear uniforms and had a chain padlocked around the ankle and everyone was observed via videotape while staying in the mock prison at the base of the campus — all to create an "atmosphere of oppression".  

On the second day itself, those role-playing as prisoners protested and those playing the role of the guards had to devise a reward and punishment system. Soon, guards grew cruel and prisoners became traumatised and depressed. Things escalated quickly and the principal investigator Philip G Zimbardo, who self-admittedly felt more like a prison superintendent than a research scholar, had to call off the experiment in six days.

Several questions were raised over the ethical and methodological grounds of the experiments, that it was the environment that made the guards behave in a cruel way. Since then, the Stanford Prison Experiment has grown infamous and has drawn a lot of flak.