George Kranky, a small boy who lives on a farm with his mother, father and grandmother, is fed up of his Grandma's selfishness, grumpiness and her attitude towards him. George seeks to cure it by brewing a special medicine to cure her (made from every harmful product in the house, and several animal medicines from his father's shed), only to end up making his Grandma as tall as a house. While this does not improve her disposition, it does make her happier. George's father Mr. Killy Kranky (a farmer) and mother come home; when the father sees the giant hen (produced by the medicine given to the hen to prove to Grandma that the reason she is that huge is because of his medicine, although this attempt is failed), he is excited while the mother is first in shock and then starts to ignore the grandmother.
George's father hits on the idea of making more of George's marvellous medicine to make his animals bigger and fatter so they can be sold for larger prices and for marketing it. Unfortunately, George cannot remember the recipe (basically because he put in everything he could find); after four failed attempts, involving some oddly deformed chickens, they create a formula which makes things shrink. The nasty Grandma, feeling ignored, thinks that the medicine is her tea and drinks all of it, shrinking to nothingness, and complaining the entire time. The mother is sad, while the father is gleeful and happy and says all is well because the grandmother was a nag; by lunchtime, the mother agrees with her husband. George then realizes that in a mere two days, he has single-handedly changed the world. Yet everyone else has already forgotten about it. The story then ends.