As other reviewers have said, this is a good overview of each of the emperors of Ancient Rome. I, however, did not find it to be an excellent reference book.
When read chronologically, the book provides fascinating facts and insights into each emperor and also into how each relates both to his predecessor and to his successor. Also helpful were the fact summarizers on the sides of the pages introducing each new emperor.
When I tried to go back and pull out information on a specific emperor to share with my students, however, I found it challenging to remember all I needed to about the previous emperor in order to follow what was being said about the one I wanted to focus on. In other words, unless being read in order, the facts are too obscure and not reviewed enough to use it as a reference book.