Starring: Song Kang-ho, Choi Woo-shik, Chang Hyae-jin, Park So-dam, Lee Sun-kyun, Cho Yeo-jeong, Jung Ziso, Lee Jung-em, Jung Hyeon-jun

Director: Bong Joon-ho

RETURNING to home turf after a run of international features, South Korean auteur Bong Joon-ho launches a sustained attack on the lifestyles of the rich and shameless with his latest Oscar winner, “Parasite.” In previous genre-driven pieces like “The Host,” “Snowpiercer” and “Okja,” Bong tapped the juicy allegorical potential of sci-fi to critique the unjust nature of capitalism and class hierarchy. This time, he ditches the metaphorical layers and adopts a register closer to social realism, albeit spiced with dark satire and noirish thriller elements. Whatever the horror-movie connotations of that double-edged title, the morally flawed monsters in “Parasite” are entirely human. Bong calls the film “a comedy without clowns, a tragedy without villains.”

With its focus on an impoverished family who concoct a wily scheme to boost their bleak prospects, “Parasite” is cumbersomely plotted and heavy-handed in its social commentary. The largely naturalistic treatment here may also alienate some of the director’s fantasy fanboy constituency. That said, this prickly contemporary drama still feels more coherent and tonally assured than “Snowpiercer” or “Okja,” and packs a timely punch that will resonate in our financially tough, politically polarized times.

From the opening scene, Bong sets up a stark visual contrast between the unequal social castes at play here. Disheveled patriarch Ki-taek (Song Kang-ho) and his family are crammed into a sunken, cluttered, bug-infested basement apartment at the end of a shabby street on the wrong side of the tracks. Ki-taek, his wife Chung-sook (Chang Hyae-jin), son Ki-woo (Choi Woo-shik) and daughter Ki-jung (Park So-dam) are all penniless and unemployed, unable to even hold down a lowly shared job folding cardboard pizza boxes. Without bad luck, they would have no luck at all.

But fortune favors the bold, especially when the bold are armed with flexible ethics and sharp forgery skills. Following a tip from a well-connected pal, Ki-woo lands a sweet job as a private tutor for Da-hye (Jung Ziso), the high-schooler daughter of wealthy corporate CEO Mr. Park (Lee Sun-kyun) and his glamorously vacant wife Yeon-kyo (Cho Yeo-jeong). In contrast to Ki-taek’s family, the Parks live high above the city in an airy, spacious, pristine modernist mansion shielded by thick concrete walls. A quick-thinking opportunist, Ki-woo spots a chance of securing jobs for his entire clan with the Parks, playing on their snobbish aspirations like a virtuoso. The plan runs smoothly, even if it means callously displacing the family’s existing domestic staff.

As it happens, there is not one big twist here but multiple small revelations and reverses, each ramping up the stakes. A deftly choreographed rainstorm sequence hammers home the impossibly wide gulf between high and low, rich and poor. Bong then makes the film’s class-war subtext concrete with a bloody struggle for survival that leaves no one holding the moral high ground.

Initially a little slow to set up its dynamic tension, “Parasite” peaks during its lively mid-section as a fast-paced, black-hearted, Coens-esque farce before climaxing with a chaotic orgy of vengeful violence. As ever, Bong’s bludgeoning attacks on economic injustice have more passion than nuance, while a superfluous coda about secret coded messages is a clumsy twist too far. A good 15 minutes of the pic’s generous two-hour-plus running time could be comfortably trimmed.

Nonetheless, “Parasite” is generally gripping and finely crafted, standing up well as Bong’s most mature state-of-the-nation statement since “Memories of Murder” in 2003. The performances are uniformly solid, with special credit due to the child and teen actors. Hong Kyung-pyo’s high-gloss cinematography combines lustrous candy-shop colors with kinetic precision, while Lee Ha-jun’s production design is typically superb, especially the elegantly minimalist Park family mansion, which serves as both deluxe fortress and sinister prison. Spliced into Jung Jaei-il’s dread-laden score, fragrant bouquets of classical music provide bustling comic counterpoint as well as wry commentary on the snooty cultural values being slowly eviscerated onscreen. (SD-Agencies)