St. Matthäus-Kirchhof Cemetery lies in Berlin, Germany. It has many historical and culturally significant graves. Four members of the Grimm family are buried there- Jacob and Wilhelm Grimm as well as Wilhelm's two sons. In A Grimm Warning, Conner, Bree, Mrs. Peters and the Bookhuggers attend a literary festival that takes place at the cemetery site, where three "new" fairy-tales by Brothers Grimm are revealed. When Conner sees the graves of the Brothers Grimm, he is surprised how plain they are, as he expected them to be "flashier".