Working title for which was probably 'Zombies on a Train'. Which may be enough to hang a film on, but this horror flick from Korea is worth a closer look for two reasons. Firstly, the tension is remarkably sustained throughout the running time. After about 20 minutes of set-up, the film is essentially a series of escalating scenarios that winnow down a train's worth of passengers to a handful of survivors. And while the in-world logic comes under some strain towards the end (an unexplained flaming locomotive appears randomly at one point to supercharge the mayhem), there's enough inventive use of the obstacles and opportunities of the setting to keep a thrill-seeker satisfied.
The second reason is that the film is actually about something more than zombies on a train. The protagonist is a fund manager who may share some responsibility for the outbreak. His marriage has failed, and he doesn't spend enough time with his daughter. When the zombies appear, he instructs her to look after number one, and not try to help others. He is contrasted on the one hand with a burly expectant dad who understands that fatherhood is about sacrifice, and on the other with a cowardly small businessman who gets increasingly comfortable with throwing others to the zombies in order to save his own skin. The film keeps coming back to this battle between self-interest and selflessness. At one point, it suggests that there may be a generational aspect to this divide – an older, more community-minded cohort who might still remember the Korean War, and a newer, more individualistic breed of Korean out to work hard, make money and leave others in the dust. It is heavily implied that the zombies are only the next step in that (d)evolution.
But if parenting is about sacrifice, the film places an awful lot of the burden on preserving a happy family on the men. All the female characters in the film are there to be put in peril and subsequently saved by the male characters – even the teenage girl, who doesn't have the excuse of being too young, too old, or pregnant, to fight. The women also don't really have arcs – they either already accept that survival requires selflessness, or are otherwise mindless paranoiacs whipped up into a frenzy by the villain. The only female character who makes a choice in the film chooses suicide in disgust at the moral compromises of her fellow passengers. She kills herself in order to kill others. Only the men kill themselves to preserve their families. Which makes me wonder how far the critique of absent fathers working long hours to support their kids goes.
At one point the burly expectant father boasts that he 'made' the baby growing inside his partner, erasing her role in the process. It's a cute moment, but the joke becomes less funny the more the film valorises his conduct.