With the hunt for Mordanti's treasure over, Nate Lowwind is just happy to be alive and among people he can truly call friends. But his freedom came at a steep cost, and not everyone is content with the price they paid. It doesn't take long for secrets to spill, and the Southern Echo suddenly has enemies at every point of the compass¿ until Rori Goodtide steps forward with a plan. Proposing the ship go west into the Forbidden Sea, Rori believes she can keep her own found family safe. All she has to do is protect the ship and crew in the face of her own demons while navigating the most dangerous waters in the world, bringing them to an island that exists on the cusp between two worlds. Rori has survived it all once before. She's determined to do it again, if only to keep her own world from falling apart. If only a sea full of monsters and dangerous weather patterns were the worst threats to the Southern Echo. As the ship sails into the west, a plot to betray Captain Arani emerges. While Rori searches for signs of the mythical Vanishing Island, Nate races to unmask the traitor before a mutiny can tear the crew apart, but it may not matter if either of them succeed. The Southern Echo is out on another voyage, and only one thing is certain: this time, not everyone will return.