Writer-director Bong Joon-ho mines a mother lode of deliciously cruel intentions in this wickedly entertaining, genre-bending satire.

Careening wildly from slapstick and scabrous social commentary to full-blooded horror, Parasite gleefully inhabits the cavernous divide between South Korea’s haves and have-nots.

The script, co-written by Han Jin-won, lulls us into a false sense of security with a gently paced yet engrossing opening hour before Joon-ho tightens the screws on his desperate characters, setting in motion a jaw-dropping second act that leaves our nerves in tatters.

The film-maker dissipates tension with staccato bursts of ghoulish humour but each belly laugh is soaked with bile – primal screams of despair at a world that repeatedly kicks the poor and disenfranchised when they are down.

“Money is an iron” notes a mother on the wrong side of the class divide, who asserts that wealth smooths out life’s creases and would undoubtedly sweeten her malodorous disposition.

With Joon-ho at the helm, any barbs are positioned with surgical precision to draw spurts of blood as the besieged protagonists stagger forlornly towards the brink of self-destruction.

Wily patriarch Kim Ki-tek (Song Kang-ho) presides over a family of con artists, including his sharp-tongued wife Chung-sook (Chang Hyae-jin), mild-mannered son Ki-woo (Choi Woo-shik) and daughter Ki-jung (Park So-dam).

They live in a squalid basement apartment in a poor neighbourhood of Seoul with a prime view of drunken passers-by urinating in the street.

The resourceful clan exploit free wi-fi to secure thankless jobs such as folding cardboard pizza delivery boxes.

It’s an unedifying hand-to-mouth existence.

Good fortune smiles unexpectedly on Ki-woo when good friend Min-hyuk (Park Seo-joon) recommends him as an English tutor for teenager Park Da-hae (Jeong Ji-so).

Ki-woo falsifies his qualifications to impress Da-hae’s wealthy mother Yon-kyo (Cho Yeo-jeong) and father Dong-ik (Lee Sun-kyun).

Once he has earned the couple’s misplaced trust, Ki-woo recommends a college friend called Jessica as an art therapist for Da-hae’s younger brother, Da-song (Jung Hyeon-jun).

Sister Ki-jung arrives in the guise of Jessica and confidently passes off theories from the internet as her personal philosophy to unlock a child’s potential.

Ki-tek and Chung-sook also seek positions under false pretences.

However, the simmering suspicions of fashionable housekeeper Mun-kwang (Lee Jung-eun) threaten to expose the ingenious deception.

Parasite is a lip-smacking delight, which divides our sympathy as moral compasses are wilfully ignored in pursuit of happiness.

The light, airy, modernist splendour of the Park family residence becomes increasingly claustrophobic as characters are enslaved to their materialistic desires.

Joon-ho retains masterful control over every element including the abrupt changes of tone in a gob-smacking second hour that proves home is where the heartbreak is.