Part action movie and part political parable, Snowpiercer is akin to Bong’s earlier films in that it starts in one genre but quickly expands its scope. (The Host was that rare monster movie that doubled as a family comedy and ecological treatise.) If Snowpiercer isn’t completely successful, it’s because the movie can’t fully transcend the familiarity of its story. With shades of Brazil and The Matrix, Snowpiercer shifts between social satire, superb action sequences, and a vaguely philosophical "The train is, like, a metaphor for civilization, man" bent. The film’s dorm-room deep thinking, however, isn’t as compelling as its gut-punch intensity and sly sick streak. (Punishment for disobedience is meted out in a creative, albeit horrifying way — and you may not want to know what the train’s leaders put in the protein bars they feed to the lower class.)

But because Bong keeps coloring outside the lines, the film is spiked with a constant sense of unpredictable dread. Assisted by cinematographer Hong Kyung-pyo and production designer Ondřej Nekvasil, the director has crafted a claustrophobic environment that goes from grungy to beautiful, the dank quarters of the lower class slowly giving way to swankier cars devoted to classrooms, nightclubs, and spas. Thankfully, though, Bong doesn’t have much interest in the whimsical fantasia of overblown stylists like Tim Burton. As a result, Snowpiercer feels lived-in rather than antiseptically, "imaginatively" rendered.

To suggest the universality of his melting-pot characters, Bong has cast from different nationalities and races, including veteran Korean star Song Kang-ho as a drug-addicted safecracker, acclaimed Romanian actor Vlad Ivanov as a relentless killer, and Tilda Swinton as a cartoonishly ineffectual authority figure dressed up in Coke-bottle glasses and fake teeth. She’s an acquired taste in Snowpiercer: mildly amusing and strange, without ever really being astoundingly bizarre.