The best laid plans of mice and men often go awry, as the old saying goes, but for four down at heels street kids even their slight attempts to evade a desperate situation land them in even more trouble than they've ever been in before. The debut feature from director Lee Sung-Tae, Derailed (Doo Namja) is bleak and gritty though underpinned by an ironic sense of love and connection which is itself often "derailed" or subverted as genuine feeling becomes a tool to be exploited in the ongoing war between those fighting among'st themselves to get a hand on the bottom rung of the ladder.
A makeshift family of four homeless kids and runaways made up of two teenage couples fights to survive in the backstreets of Seoul. With no practical means to support themselves, Jun-Il (Minho), his girlfriend Ga-young (Da-Eun), friend Bon-Gil (Lee You-Jin) and Bon-Gil's girlfriend Min-Kyung (Baek Soo-Min) are often forced to resort to low-level crime just to get something to eat. Running low on supplies the gang try to steal a car but the plan goes awry when an old enemy, the former boyfriend of Ga-young who blames Jun-IL for the prison sentence he's just been released from, arrives prompting the gang to flee.
Out of options their next plan is a dangerous, possibly unpleasant one – a prostitution scam. Ga-young being a little braver than Min-Kyung puts herself forward as the bait and waits for a randy guy with underage tastes to pick her up in a dingy back alley before taking her to a hotel. Once there she needs to text the boys who will march in, rescue her, and blackmail the John. What they didn't reckon on was that their target would be a big guy and a petty thug operating on the fringes of the sex trade. The boys manage to knock the irritated bruiser, Hyung-Seok (Ma Dong-Seok), out and the gang steals his wheels too but they've messed with the wrong guy. Hyung-Seok calls his buddies, tracks them down, roughs them up and then makes them an offer they can't refuse. In payment for the damage, inconvenience, and humiliation, Ga-young can work off the debt in one of his "karaoke bars". Or, he could break Jun-IL's face, choice is theirs.
Jun-IL begins the film with a voice-over about his life on the streets. "Being nice is being stupid" he tells us. He has a point. When you're trapped at the bottom it's every man for himself, you can't trust anyone and kindness is always a weakness. Yet Jun-IL is "nice", in a sense. The unofficial daddy of the group, he takes care of the others and refuses to leave anyone behind, hungry, or afraid. It's no surprise then that he feels so personally responsible for the fate that's befallen his girlfriend, Ga-young. Despite Ga-young's pleas to keep himself safe and take care of the others, Jun-IL goes to great lengths to try and get the money to buy her back by paying off the impossibly high debt.
Hyung-Seok, despite running a chain of seedy "karaoke bars" which straddle the line between providing female company and outright prostitution is also a committed family man with beloved teenage daughter of his own. Apparently, Hyung-Seok's business enterprises have taken a tumble recently, enough to have his wife complaining though it seems unclear if she knows exactly what her husband's line of work entails. This crisis could not have come at a worse time for him but even if he expresses surprise, concern, and mild outrage that Ga-young's mother tells him to get lost when he threatens to harm her daughter unless she pays up, Hyung-Seok does not seem to see the link between this vulnerable teenager and his own elegantly attired little girl.
To make matters worse, Hyung-Seok eventually teams up with the gang's arch nemesis, Ga-young's ex, to destroy the band of four as thoroughly as possible. The eventual intervention of the police is perhaps useful and well-meaning, but merely adds another motivating force to this already complicated set of intersecting vendettas. Trapped between a traumatic past and a hopeless future, these are kids whose lives have become so completely derailed that there is almost no possibility of righting them. Family betrays, love fails, friendship collapses, being nice is being stupid but in a world filled with so much corruption it might just be the only chance left.