Deep in the ocean's darkness live the Merwin, sinister sea creatures who have never seen the light of the sun. As the city of Mervidia flourishes, its inhabitants scheme and grasp for power. Queen Beryl, the last of the royal bloodline, has been brutally assassinated. The High Houses scramble to seize Mervidia's crown, posturing for rank and the possibility of having a race other than the ethyrie wear the Fangs for the first time in Merwin history. The blood of a nation is spilt, turning kin on kin and house upon house, all in hopes of sitting on the throne and ruling the Deeps.