Nils is the main protagonist of the series. He lives with his family on a farm in southern Sweden. Nils is lazy and disrespectful to his fellowman and enjoys abusing animals in his spare time. After the farm's tomte magically shrinks Nils he become much smaller than all the animals and is capable of speaking and understanding animals language. Since all of the farm animals are out for revenge, Nils travels with a flock of wild geese which is flying to the north of Sweden for summer. Nils wishes to transform back to his original size.