The Stanford Prison Experiment was a psychological study conducted in 1971 by Philip Zimbardo that aimed to investigate the psychological effects of perceived power and roles. For the study, volunteers were randomly assigned to be either prisoners or guards in a mock prison located in the basement of the Stanford psychology building. The experiment unfolded quickly, with guards enforcing authoritarian control over the prisoners through intimidation and humiliation. By the third day, prisoners began emotionally breaking down and losing their identity, while guards increased abusive tactics. The experiment was abruptly ended after only six days due to the levels of psychological cruelty and emotional distress observed in the prisoners. Zimbardo concluded that situational forces and roles can strongly influence human behavior.