Is poverty inescapable, and are its symptoms self-wrought? Must the poor stoop to extreme measures just to get by, and do the wealthy have an ethical obligation to take notice and maybe do something about it? Filmmaker Bong Joon-ho (The Host) raises these and scads of other questions in his newest, Parasite, a semi-comedy, semi-dark parable examining the lengths to which one family will go to survive.

We follow Kim Ki-woo, (Choi Woo-shik), a college-aged youth who unwittingly scores a job tutoring English to the daughter of the wealthy Park family. Kim's family has slipped into a sort of default conman mode, and he must fake credentials in order to keep his position. Soon after, his sister (Park So-dam), mother (Jang Hye-jin) and father (Song Kang-ho, a regular Bong collaborator in films like The Host and Snowpiercer) have all weaseled their way into various jobs for the Parks, and life seems doable for possibly the first time ever. But when a former employee returns in search of something she left behind, the comfy jobs transform into a hellscape, wrenching security from the Kim family and spiraling everything out of control.

Bong's eye is, as always, masterful, from the more overt symbolism based in modern-day classism to the subtler moments and examinations of insanity, even if it's temporary. Each character proves a powerhouse on their own, but the ensemble dynamic of the Kim family feels so natural and comfortable that we find reasons to empathize even when they're at their worst. Song in particular carries the film in the background with a commanding performance as a desperate father pushed to his very limits. Elsewhere, the Park family's innocent yet irritating cluelessness starts to make us wonder if vilifying the rich always makes sense—they're not bad people, they're just blissfully ignorant of the goings-on in their own home.

Parasite morphs so suddenly and jarringly that it becomes a breathless dash to the finish line. Bong brings us to the brink of unforgivable, but keeps us grounded enough the entire time that we can sympathize with every character, even as they do seemingly dastardly things. Pity, then, that it begins to lag once the major conflict kicks in. The final 30 minutes, which could have reveled in sheer chaos and nearly do, feel more like a sudden drop in pacing than they do a satisfying conclusion. It isn't even that satisfaction is mandatory, rather that Parasite's ending feels more like a tacked on series of events. The journey to get there is riveting, but it surely seems like Bong felt he needed to hedge his bets in an otherwise fantastic tale.

+Thrilling buildup; exciting performances throughout
-Disappointing payoff

Directed by Bong
With Choi, Park, Jang and Song
Center for Contemporary Arts, Violet Crown, R, 132 min.