Watch Sadistic Stanford Students Play Role of Guards at Fake Prison, Abuse Fellow Students

In one of the most notorious experiments ever conducted, students at prestigious Stanford University were locked up in a make-believe prison as other students acted as prison guards.  

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Now a new movie, The Stanford Prison Experiment, tells the inside story of the experiment and how the guards turned into sadists.

“This is all real. They won't let you go. They won't let us leave!” said a student.

“It's disturbing but it so faithfully reproduces what I did in my study 44 years ago,” psychology professor Philip Zimbardo, who created the experiment in 1971, told INSIDE EDITION. He's played in the movie by Billy Crudup. Zimbardo said watching it brought back bad memories.

“It recreates the guilt I felt in allowing the study to go on too long. That's the only painful thing,” he said.

The experiment has gone down in history as a test case of how even decent people can turn into monsters.

The guards began abusing them from day one. They put paper bags over their heads to disorient them.

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Professor Zimbardo was condemned for failing to step in right away. He said he liked the movie and attended the premiere. He says there are important lessons to be learned from his  controversial experiment.

“We proved the point: situations can overwhelm even good people,” he said.

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