Quinn Wexford and Kayla Livingston have pinned their hope for answers to Quinn's Great Aunt Tally, but those hopes are crushed when they find a terrified shell of the feisty old woman they expected. While continuing to search for their missing siblings and trying to protect Great Aunt Tally, they work to discover who they are, but instead learn disturbing answers to questions they didn't know to ask. Hidden messages and out-of-this-world helpers lead them to a pirate treasure that's been hidden for three hundred years. But the cost is high and this time, they're afraid they won't get out alive.