This is the second book in the Ruby Throne Trilogy, and although I remember the first book being great, I enjoyed this book is MUCH more than the first.
The first book, Reign of Shadows, set up the foundation of the story, characters, plot points etc which meant that this book was able to get right into the action. We see Elandra crowned Empress and have some interesting trials whilst on the path to prepare for her coronation. We also see some changes in Caelan's life too - Risen to fame due to being the Prince's Gladiator, he discovers the Prince is a traitor and they get into some trouble. Caelan ends up getting tortured - it seems like his life has gone back to square one. That is, until he joins the Emperor's army. Then he must help fight when the empire is attacked.