Felidae (novel) many contemporary ethical problems and philosophical questions, such as the relationship between mankind and animals and the idea of superior races within species. Thus, the "Felidae" series can be considered more complex and multi-layered than many contemporary crime novels. The novel begins with Francis, a tomcat, moving to a new neighborhood with his owner. Francis soon finds the corpse of another local cat, Sascha. Bluebeard (Blaubart in the original print), a deformed local cat, is convinced that humans(cat slang: "can-openers") are responsible for the death and other recent murders. Francis disagrees with this assessment, convinced that the slash on Sascha's
Felidae (novel) murderer, and that Joker's name was eventually cleared. Jesaja was coaxed out of the catacombs, and has found a home with a bartender. Francis muses that Claudandus had succumbed to hatred, lost his innocence, and in the process, became human. He states that all animals have the ability to lose their innocence and humans, who descended from animals, still carry a hint of innocence. The novel ends with Francis urging the reader to never cease believing in a world where all animals and humans coexist, including those "more sublime and intelligent than the latter--for example, Felidae." In Germany, "Felidae" became