A mysterious virus has infiltrated the good people of Lake Wobegon, transmitted via unpasteurized cheese made by a Norwegian bachelor farmer, the effect of which is episodic loss of social inhibition. Mayor Alice, Father Wilmer, Pastor Liz, the Bunsens and Krebsbachs, formerly taciturn elders, burst into political rants, inappropriate confessions, and rhapsodic proclamations, while their teenagers watch in amazement. Meanwhile, a wealthy outsider is buying up farmland for a "Keep America Truckin" Motorway and Amusement Park, estimated to draw 2.2 million visitors a year. Clint Bunsen and Elena the hometown epidemiologist to the rescue, with a Fourth of July Living Flag and sweet corn feast for a finale.