The assassination of a king means Prince Ang receives an early promotion. The new king is just a boy, and has a lot to learn about ruling. In fact, he has a lot to learn about everything. He has advisers, but one of them may be trying to kill him, to finish off the royal line. Nelson and Seaview must get the prince back home so he may take the throne and prevent a coup from leaving an unfriendly government in power. Fortunately, a mysterious sailor, Old John, appears along their way and helps the young prince. But exactly who is Old John?