Katharine was getting more and more powerful in the previous part thus now she has become the queen she has always dreamed of. Being the queen gives a cool feeling but only if all the threats to the throne are removed permanently. Unluckily Katharine does not possess this luxury at her hands. All the evidence that she has gathered gives her the clear picture that her sisters are dead but her heart does not believe in this clear picture. She has not seen the dead bodies so she thinks that they are out there somewhere planning for her destruction. Mirabella and Arsinoe are present far from their native land but they are planning nothing.
They think that they were lucky enough to survive. Both the sisters are regularly disturbed by the visions that they start having almost on the same day. The visions associated with the Blue Queen forces the two sisters to return to the land for another fight against their sister. Characters like Jules and Mathilde also play their roles well, they were not there in the main story during Three Dark Crowns and One Dark Throne.
Chaos comes to the world of the three sisters once again and perhaps this time all of them would have no other option rather than confronting the enemy together. This time author Kendare Blake and the narrator Amy Landon just ignite the spark in the minds of the fans to know about the conclusion of the series as early as possible. The last part just cannot be left because there is so much that needs to be answered properly in the conclusion.