Martha Flannery, an aggressive missionary, sets out for the Phrasian Islands to convert the newly discovered tribe called Ranu. Here she enters a strong battle of wills with Dr. Connors, a cultural anthropologist who wants to protect the Ranu people from any outside influence, especially evangelism. Connors' strange manners and obsession with the Ranu are only the first of several eerie mysteries, including previous visitors to the island who never returned home and an elderly gentleman claiming to be four thousand years old.