Curses, secrets, and magical powers rule over the kingdoms around the Agata Sea. When Princess Beatriz falls in love with an enemy prince, her Papá refuses to allow a betrothal unless they can turn it into a treaty. But even her kingdom's current alliances sit atop a knife's point when her brother's anticipated nuptials don't transpire. Instead, their allies make secret deals for the promise of magical relics. Through investigation, she discovers that the same people who prevent the treaty are also the same ones who poison other allied kingdoms. To make matters worse, her best friend and beau keep secrets from her. Beatriz and her brother take to the sea on a secret mission to expose their hidden enemy and uncover what everyone isn't saying. What they find will test the limits of their magical abilities and everything they hold dear.