Topsy-Turvy gets a new resident, pig Greta moves in! Wolf, Rune and Rabbit immediately get curious. Who is she? Does she like cakes? What if she is too shy to make contact with her new neighbors? What if she thinks Wolf, Rune, Rabbit and the others are dumb? The three friends decide to fix a surprise party, so that Greta realizes she has moved to the world's best city. Everyone in Topsy-Turvy want to help with the preparations.
At the end of the book there are suggestions of simple crafts for those who want to fix their own party!