A scene from The Stanford Prison Experiment (IFC Films)

It’s no small feat to take a 45- year-old social science experiment and turn it into a fresh, compelling, timely film, but that is exactly what the filmmakers behind The Stanford Prison Experiment have done. In the summer of 1971, Stanford University psychologists, led by Dr. Philip Zimbardo (Billy Crudup), selected two dozen students to play the roles of prison guards and inmates. The result is a disturbing, realistic portrayal of how malleable the human personality is to its environment and circumstances.

Like so many independent films, this one takes place almost entirely in the same series of small spaces, in this case, a cramped hallway and a few empty offices and classrooms. While some of these films can feel stagnant as a result, like the recent Faults, which takes place almost entirely in a hotel room, Experiment uses sound design and an energetic camera to make the location feel bigger than it is. The action rotates fairly evenly between the guards, the prisoners, and the researchers throughout their eight-hour shifts, keeping scenes fresh and propulsive.

The shift in perspective deftly makes viewers into objective observers, like the researchers, aghast at how quickly the power dynamic in the fake prison spirals out of control. Viewers also feel building dread when the comparatively benign guards are about to go off duty, and the shift of the more abusive guards begins. We are taken into their heads as well, feeling the swell of authority and purpose that comes along with changing out of civilian clothes into khakis, putting on aviator glasses, and swinging a nightstick. Even the prisoner’s role is occasionally made attractive, as a groundswell of revolution builds and escapes are planned.

Part of the reason it seems more epic than a film taking place mainly in a drab hallway should is that it isn’t afraid to let its key players go through full, chaotic transformations and completely flame out early in its running time, so it feels like a whole lot happens. Most films would treat actors of Ezra Miller and Tye Sheridan’s caliber as stars to carry the entirety of the story, but here they are allowed to complete fiery arcs while the film carries on.

As good as Miller and Sheridan are as two of the more distressed prisoners, the unquestioned star is Michael Angarano as guard Christopher “John Wayne” Archer. From the second he dons his guard costume, he completely transforms into a seasoned veteran correctional officer. He projects total confidence and authority over the prisoners and the other guards as well so that they don’t take issue with his largely unnecessary totalitarian flourishes. Archer had obviously never worked as a guard before, and could have just as easily been a prisoner if Dr. Zimbardo’s coin flip deciding the roles had gone the other way. Without the experiment shaking out as it did, he would never have known he had this masterful savant of control lurking inside him.

The word “experiment” is in the title, but there is little analysis or academic reflection to be found. Viewers are left to piece together the larger meaning for themselves. It is foremost a full-on simulation of prison life, with Dr. Zimbardo and his researchers trying in vain to keep up with the remarkable, unanticipated developments. At one point, a colleague nonchalantly asks Dr. Zimbardo what the independent variable in his experiment is. He responds with indignation, partly because he doesn’t want his research questioned, and partly because he probably doesn’t have an answer. There is only a thin veneer of the academic in Zimbardo’s experiment—it is primarily an opportunity to allow the underbelly of the human personality to have free reign.

The Stanford Prison Experiment is a powerful, engrossing depiction of the interplay between individuals, institutions, and power, and an unsettling reminder that we can never know what we’re truly capable of in every circumstance. There could well be a monster lurking inside us that we thankfully are unlikely to confront.