Crown of Midnight is the second book in the Throne of Glass series by Sarah J Maas. It continues the story of Celaena Sardothien aka Elantiya, who won a contract to be the King of Adarlan’s champion, aka assassin, in the first book, Throne of Glass. Now, Celaena spends her days stalking and killing the King's enemies but what we soon discover is that she has been secretly faking their deaths and sending them away. This puts not only her own life in jeopardy but the king has also threatened her best friend the Captain of the Guard Chaol and her other best friend Princess Nehemiah and both their families if Celaena doesn't do her job as he desires or fails to return from a job.