Based on the cartoon by Swedish writer Astrid Lindgren. In the city of Stockholm, on the most ordinary street, in the most ordinary house lives the most ordinary Swedish family by the name of Svanteson. This family consists of the most ordinary dad, the most ordinary mother and the three most ordinary guys - Bosse, Bethan and Kid, everyone's favorite, whom everyone spoils as soon as possible. But on one of those unfortunate days, when nothing brought joy to the Kid, an unusual story happened to him - he met the "best in the world" Carlson, who lives on the roof...