Twelve-year-old Jess and Jude live a dream life on a yacht, sailing from one exotic destination to the next with their guardian, Captain Gabe Carter. But when Gabe vanishes one night after an argument with a stranger, the twins are left alone, facing an incoming storm and an unknown enemy. Surviving at sea is just the start of an adventure that will take them across oceans and pit them against one of the world's most powerful men. How far do they dare go, and what will they risk, to find the truth about who they are really are?