In Inspector Renard's office in Paris, he receives important news: his old adversary, Hiéna, a well-known plunderer of Europe's museums and private collections, is about to launch a new operation in the Hungarian capital. At the same time, the journalist mother of a high school girl disappears without a trace in Budapest. Bora suspects that her mother has been kidnapped because she has come into possession of information that should never have been leaked. The French inspector arrives in Budapest to catch Hiéna in the act, and enlists the help of the Hungarian police. Bora is determined to find his mother, while he and his class are supposed to be researching the history of the Matthias Church in Buda as part of a history project.

In this thrilling thriller by Judit Berg, József Attila József Prize-winning author of "Hisztimesék" and creator of Rumini, Alma and Drifter, the characters stumble upon interesting facts and events from history and art history, as the lives of two detectives, a few criminals and a group of determined Hungarian high school students intertwine for ten days, so that all the pieces of the puzzle fall into place at the end of a story that is sometimes funny, sometimes frightening and full of unexpected twists and turns.