Some jobs just suck. Positions that often come up on the worst jobs ever list include working in fast food, cleaning, pest control and roofer.

This South Korean film chooses another profession that is often high on lists, and that’s customer service adviser, as a young girl starts her working career unaware of the pressure that comes with it.

Sohee (Kim Si-eun) has reached that point in her education where her school sends her out on an externship, which could lead to a full time position. Her school advisor is very excited for her as he has secured a place in one of the biggest companies in the country for her, S-Plus Korea Telecom.

She is excited at the prospect but soon becomes disappointed when it’s not quite the dream job it’s made out to be; she is placed in a call centre in customer service, where she is on the phone to customers all day. But even then it’s not that simple; what she actually has to do is try to not only persuade disgruntled customers to stay with the company, but lock them into even longer, more expensive contracts.

Her income is also tied in to how well she does; if she hits the targets, it means she could do well, but if she doesn’t, it doesn’t look good. But in reality it doesn’t even work out that way, as she is paid way less for being on an externship, and having signed a number of dubious contracts.

It’s a position she soon discovers that is fraught with tension, that has a negative impact on not just her mental health, but all her other colleagues, with one even taking their own life.

It’s a job that doesn’t end well for Sohee, which leads to an investigation by Detective Oh Yoo-jin, for whom what should be an open and shut case, ends up taking some unexpected turns.

It’s taken a while but this is South Korean director and screenwriter Jung Joo-ri’s follow up to her 2014 film A Girl at My Door. It’s an intriguing film, with the majority feeling like a character-driven piece, focusing on a young woman’s struggle with a harsh working environment.

So for two thirds of the film we follow Sohee, played superbly by Kim Si-eun, as she comes to terms with the difficult transition from education to work. We know she has a passion for dance, and that many of her friends are in similar positions where work is concerned.

Then there’s a curious pivot, where the final third sees the detective trying to pick up the pieces. With this pivot comes a shift in tone, with most of the film focusing on the unjust system that Sohee finds herself in, and then tagged on at the end the detective uncovers similar truths.

It’s all told at an incredibly slow pace, with building the profile of character of the young woman a clear priority over story progression. So much so that the inclusion of the detective comes across almost as an afterthought. But even with her arrival, the pace never manages anything more than a plod.

But despite taking its time, the performances are well-rounded, especially that of Kim Si-eun, who is particularly spell-binding.

It’s a film then that doesn’t necessarily fulfil its potential, but it’s clear that its director isn’t one for compromise.

It is a little too long, and although it sets up an interesting premise, with a great central performance, its story and its focus could have done with a little more attention to get the most out of it.