In 1775, on a long-haul passage from Bombay to England, two young Britons, Anne and Tobias Middleton, form an enduring friendship with an ailing midshipman destined one day to be a hero. As the ship makes its way around the southern tip of Africa, Anne, Tobias, and Horace encounter a malevolent mystery aboard. Something evil is invading their dreams. And as the days progress, it is getting stronger. The trio must discover the source of the discordance and figure out how to put a stop to it, before something dreadful occurs -- something they may not survive.