There are many things art can do, and one of the most essential is help us understand ourselves better as human beings: communicate or explore ideas in a way that’s more compelling, or usefully different, than just stating the ideas literally.

Craig Zobel’s highly controversial new film Compliance—it’s not yet in wide release, but people have walked out of film fest screenings yelling in protest—begins with an unmissable and non-ironic notification that the film is inspired by actual events. Those events were dozens of incidents where fast-food restaurants and grocery stores were victims of a criminal hoax. There were variations on the hoax; Compliance is based on a 2004 incident where a female McDonald’s manager in Kentucky spoke with a male caller claiming to be a police officer. The caller convinced the manager that a teenage girl in the restaurant’s employ had been accused of theft, and through an insidious combination of strategies including threats, charm, and the leveraging of bits of information disclosed by the restaurant workers, convinced the manager to participate in an escalating series of abuses that included a strip search—and, horrifically, more.

It didn’t take a sick prank to demonstrate that people are capable, with surprisingly little encouragement, of doing things they would never have believed they’d do: in the early 1960s, psychologist Stanley Milgram proved that subjects encouraged by an experimenter would administer electrical shocks that they believed were strong enough to be life-threatening. (The shocks were not actually administered, but the subjects believed they were actually happening.)

A decade later, psychologist Phillip Zimbardo conducted the Stanford Prison Experiment, a role-playing study in which subjects assigned to the role of “prison guard” began to act so brutally that the experiment had to be stopped. The caller (Pat Healy) in Compliance knows what Zimbardo learned: strip a person of her identity, and she’ll be more pliant than you (or she) might have believed possible.

If Compliance was nothing more than an effective updating of Milgram and Zimbardo, that would be reason enough to see it. But the film goes further, illustrating a range of truths about human behavior that we would like to believe are false.

Beyond the fact of our sometimes misplaced trust in those we believe to be in authority, there’s the reality of America’s class system. The fast-food workers depicted in Compliance are economically vulnerable: they can’t afford to lose their jobs. Becky (a riveting Dreama Walker), the girl accused, is reduced to tears at the suggestion that she allow virtual strangers to see her naked—but they’re strangers who could fire her or send her to jail, and so she complies.

Then there’s the frog-in-the-frying-pan syndrome, one of con artists’ most reliable and useful tools. If you can lead a subject up to a certain point by small increments, her resistance to taking further steps is reduced as she starts to realize that she’s done things based on beliefs that she now can’t afford to be false. Just as people keep sending more and more money to long-con scammers in the desperate hope that the money they’ve already sent isn’t lost forever, the characters in Compliance continue to follow orders even as they start to realize that there’s a very good chance that is not actually a cop on the phone—the idea that they’re being victimized is so unthinkable that they will themselves not to think it.

The fact that Compliance is a movie, one that holds viewers as rapt as any, is the final twist of Zobel’s cunning knife. Writer/director Zobel encourages the audience to root for Becky’s friend (Philip Ettinger) to call the prankster’s bluff, but also shows us the prankster’s perspective. We see Healy on the phone: Zobel portrays him as creepy, yes, but also shows that to the caller, the con is a fascinating and thrilling game that he’s very good at playing. As Healy’s character, “Officer Daniels,” keeps raising the stakes, Zobel allows the audience to taste his thrill at each little victory. As you watch the action unfold, you’re apt to experience a surprisingly wide range of thoughts and emotions—which is precisely the point.

Compliance would be abominable rather than admirable if not for Zobel’s manifest respect for his characters. The events that unfold could be the basis for a particularly unseemly porno, but Zobel wrote sensitively and cast well, with the result being a film that feels painfully plausible. Restaurant manager Sandra (Ann Dowd) feels like a person you know: working hard and hoping for the best, acting with the best intentions but failing, tragically, to do what is right rather than what is convenient when the restaurant is busy and she doesn’t think she can afford to doubt the caller’s story.

Events near the film’s conclusion begin to feel extreme, and they are—just as most of Milgram’s subjects stopped before delivering the most painful shocks, most of the actual restaurant workers who received calls like this stopped before things reached the point they reach in the film. But things like this do happen—and did happen. (An ABC report on the Kentucky case, featuring surveillance video of the incident, demonstrates that if anything, the actual situation was even more appalling than depicted in Compliance.) Sadly but surely, things like this will happen again.

You haven’t (I’m presuming) been involved in anything nearly as extreme as what happens in Compliance, but Zobel’s restaurant workers aren’t wired fundamentally differently than you or I are. All of us have obeyed authorities—legitimate or illegitimate—in ways that we’ve lived to regret. All of us have allowed a bad situation to get worse because we’re not brave enough to take action to stop it. The haunting resonance of the character implicated in the film’s climactic atrocity (a character treated by Zobel more humanely than his real-life counterpart seems to deserve) is that, though we haven’t done that, we’ve all allowed ourselves to believe something we should have known better than to believe, simply because we wanted it to be true.

The title of this post may sound like hyperbole, and I’m not saying Compliance is a perfect film. But I’m confident this will be a movie people will come back to again and again in years to come. It asks some very hard questions about human nature—questions that it leaves unanswered because they’re questions each person can only answer for himself or herself. To dismiss Compliance as extreme or exploitative is to ignore the fact that right now all of us are trusting someone we shouldn’t trust, believing something we ought to be doubting, and doing less than we can to stop someone from getting hurt. That’s the very real horror of this deeply unsettling, absolutely essential film.

– Jay Gabler