Many years ago, I used to work at a cinema – a multiplex chain, complete with bouncing hot dogs, baseball cap, coloured shirt and name badge.

It wasn’t in, shall we say, the nicest of areas. The kind of place where they put metal detectors over the entrance to a cinema screen, where people would break into fights after being caught trying to steal pick’n’mix. The kind of place where, after I was promoted to “Supervisor Ivan”, customers thought that “Supervisor” was my first name. And stopping an under-age child trying to see 15-certificate film was automatically branded racist.

But worse than that were the working conditions. With the employee rota cut by head office for financial reasons, the understaffed cinema had to deal with thousands of people every Friday and Saturday night. The result? Long queues, angry complaints, an exhausted Ivan and not enough breaks for staff members. Usually, no breaks at all.

I made it clear that I wasn’t OK with that, but I was still required to go and tell staff that they wouldn’t be able to have a full lunch or dinner. Did I say no? More than I'd like to admit, no. I was caught in the middle, obliged to go along with orders from management, even though they also meant no breaks for me.

But that’s nothing compared to what happened to Becky (Walker) and her boss Sandra (Dowd). Halfway through the busy shift at Chickwich fast food restaurant, Becky’s boss gets a call from Officer Daniels (Healy). It turns out that Becky has stolen money from customer and that the police are on their way. So Sandra has to detain Becky in the back room until they arrive. Alone. With her clothes off.

Based on real events, Craig Zobel’s film Compliance (out this week) follows the escalating demands of "Officer Daniels" - and Sandra’s shocking capitulation. First, it’s a pocket search. Then, her bag. Then… well.

Expertly edited, Zodel cuts away from exploitative moments to focus on bubbling fat and greasy chicken, playing up the dirty seediness of this deep-fried temple of servitude. The result is an agonizing, excruciating, horrifying piece of manipulation – slow-burn cinematic torture sold wholesale by Ann Dowd’s awkwardly obedient middle manager.

It’s not an easy watch, for sure, but it’s a powerful one; a nasty look at human nature that surprises right up to the final frame.

Some have criticised the film for spinning the scenario out for too long - missing the point of the film entirely. Does it stretch the premise beyond believability? I’ve got a baseball cap and a name badge sitting in a wardrobe somewhere that say otherwise.

Compliance is out in UK cinemas on Friday. Go and see it. I dare you to say no.

Read our Compliance review from the LFF.