As it begins, The Inner Life of Cats follows the development of the young Augusta while simultaneously explaining the basics of a kitten's physiological and psychological development. As the narrative progresses, McNamee also charts cats' evolution, explores a feral cat colony in Rome, tells the story of Augusta's life and adventures, and consults with behavioral experts, animal activists, and researchers, who will help readers more fully understand cats.

McNamee shows that with deeper knowledge of cats' developmental phases and individual idiosyncrasies, we can do a better job of guiding cats' maturation and improving the quality of their lives. Readers' relationships with their feline friends will be happier and more harmonious because of this book.