Shadow and Tide — Rachel Greenlaw

Bargains made in desperation have steep costs.
Mira has been listless on Rosevear, waiting for the moment that she can join Elijah, avenge her father, and put a stop to Seth and Renshaw's schemes. But, before she can take action, the watch strike and leave devastation in their wake.
With a crew of loyal friends, Mira makes plans to cut down Renshaw's reach with the use of her mother's map. Though Elijah is worried about the word of Mira's ability spreading, she's determined to stop the people threatening her island. But, as she learns more about Renshaw's plans -- her control over the watch, and other allies in high places -- she realizes that danger surrounds her on every side.
Mira might be in over her head, but after surviving so much betrayal, will she be able to trust Elijah and his crew in order to save herself, her homeland, and the people she loves most?