What will they sacrifice to save their kingdom? Their honor? Their love? Their lives?

Tessa Cade has gone from masked outlaw to palace advisor, but even with her newfound power, she cannot stop the sickness still raging. As the kingdom's supply of Moonflower elixir dwindles, Prince Corrick attempts to find a new way to lead, struggling to repair the rift between the royals and the people—and the one growing between himself and Tessa.

When an emissary from a neighboring kingdom arrives with an intriguing offer, Tessa and Corrick set out on an uncertain journey to find a new source of the lifesaving elixir. With tensions brewing on deck and the sea swirling below, they must decide who they can trust, only to discover that a betrayal may be much closer than they think.