While investigating a toxic outbreak in the Caribbean Sea that could threaten the United States, Pitt unwittingly becomes involved in something even more dangerous: a post-Castro power struggle for the control of Cuba. Meanwhile, Pitt's children, marine engineer Dirk and oceanographer Summer, are on their own investigation, which brings them to Cuba too, and squarely into harm's way. The three have been in desperate situations before, but perhaps never quite as dire as the one facing them now.