The_Ploughman’s review published on Letterboxd:
Characters traveling to higher and lower ground depending on their circumstances makes sense literally and metaphorically, like the pertinent phrase "shit rolls downhill." Maintaining this balance puts the film in a place between satire and thriller, an area it occupies without shortchanging either side.
Like the family of last year's Shoplifters with their audacity dialed up a couple notches, the impoverished Kim family relies on daily hustles to survive. Their hustle is a one-by-one usurpation of the household help for the wealthy Park family. The Parks are susceptible to this hostile takeover. Years of easy living in a gorgeous mansion has dulled their senses - except, importantly, their sense of smell that threatens to ferret out the lowly nature of the Kims. In one of the movie's many observant jokes, the research and effort required to keep up the ruse falls short of earning expertise but does require actual work. The line between con and basic employment is a thin one, Parasite suggests.
Not all of the Parks' employees go quietly and the scene where the family discovers the stakes for one they replaced is the point the movie kicks into overdrive. Even if we can tell in the broad strokes where this is headed, Parasite keeps turning to the end and the camera and lighting have an irresistible playfulness that twists cringes into grins.
Considering the success of Us and this film, the upper classes should take note of the number of people coming up from lower altitudes to invade their homes.