Parasite

A poor Seoul family systematically infiltrates the household of a wealthy one — one member at a time, each posing as an unrelated professional. Bong Joon-ho builds the first half as a dark comedy of class aspiration, precise and very funny, then pulls the floor out completely. The house itself is the film's real argument: who gets to live above ground, who gets buried below, and the violence required to maintain that arrangement. Won both the Palme d'Or and the Oscar for Best Picture.