Darkness and isolation are the two constants in “Coin Locker Girl,” the feature-length debut from director Han Jun-hee. It is a crime drama ― violent, unpredictable and thrilling, but even amid its unexpected twists and turns the film never strays from its central message: life is a hard, solitary endeavor.

That theme is counterintuitive to the fact that the central characters in the film call each other a “family” despite having no biological connection. In fact, it isn’t clear at first what the relationship between these characters is, or what they do together.

“Since this is a noir crime movie, I thought that the audience would develop prejudices about the characters if I showed what they do for a living from the beginning,” said director Han, speaking at a press preview at CGV Wangsimni on April 20. “I wanted the audience to see them first as a family. A strange family.”

Heading the family ― which is later revealed to be a vicious crime ring specializing in loans and organ trafficking ― is Mother (Kim Hye-soo), a cold, calculating woman who rules the dark underworld of Chinatown in Incheon. She has two “sons” and two “daughters,” her henchmen who scatter across the city to collect loan payments and to beat and torture defaulters.

There is no camaraderie in this family, no current of loyalty that underlies the blood-stained transactions. Mother tells her children repeatedly and outright, “When you become useless, I’ll kill you.”

Of the children, the film focuses on Il-young (Kim Go-eun), a girl whose name means “1-0” ― named for the number of the coin locker she was abandoned in as a baby. After she is sold to Mother as a child, she methodically carries out Mother’s horrific commands to stay alive. She never questions her place ― until she meets Suk-hyun (Park Bo-gum), the son of a debtor who shows her kindness and a life other than the one she has known.

However, through a series of events Il-young is taught once again that she can lean on no one, that she can only trust herself in this dog-eat-dog world. In essence, she comes to understand Mother’s state of mind, and the audience realizes that Il-young is becoming the woman she hates so much.

Throughout the film, the audience is teased with plot developments that never quite pan out the way they’re expected. There is no big moral or turning point, when darkness turns to light, or Mother finds her humanity. Chinatown always remains Chinatown, full of despair. The stark picture of the futility of hope is emotionally tolling, but captivating all the same.

“Life is always hard, with just a few good moments to keep us going through the hard times,” said Han. “I chose this particular town, with its unique colors, because I felt it reflected that sentiment best.”

Han’s choice to have the events of the movie unfold in two leading female characters ― an unusual decision for a crime drama ― was also a conscious one, designed to amplify the mercilessness of life.

“I think that women are stronger than men. They don’t make excuses for themselves, and they don’t have regrets,” he said. This strength, embodied in Mother and Il-young, are a welcome departure from the typical role female characters have played in past crime dramas. They are not dependent on the men around them; in fact, they do not and cannot depend on anyone, and rely solely on themselves for survival.

“Coin Locker Girl” is a fast-paced movie dotted with violence, yet it feels heavy and methodical because the audience realizes intuitively that it will be consistently dark and despairing until the end. This impressive debut from Han Jun-hee ― invited to the Semaine de la Critique at Cannes this year ― opens in local theaters Wednesday.

By Won Ho-jung (hjwon@heraldcorp.com)