As the official chaplain of a major Seattle medical complex, Raff — now Father Rafferty — attends to the spiritual needs of victims of a lethal and previously unknown viral disease believed to be caused by a mysterious organism known as HH-256. Fired research physician Dr. Amir Hallaby confides to Raff that he suspects that rival researcher Dr. Henry Hammel is behind the spread of the virus via deliberately contaminated vaccines manufactured by a pharmaceutical company owned by Hammel’s close friend, Anja Kramer, with whom he appears to have an uncertain relationship.

Despite his vow of celibacy, Raff finds himself attracted to the seductive and attractive Anja, whom he suspects may be part of an international conspiracy to wipe out targeted Third World population groups who oppose the ambitious, but dangerous plans of Swedish magnate Sven Olafsson to exploit their respective countries.

Olafsson is a close associate and major donor to the research work of both Hammel and Kramer. When Dr. Hallaby is murdered in a bizarre and gruesome fashion after having informed Raff that he is close to finding a drug to effectively combat HH-256, Raff is determined to get to the bottom of the crime as well as helping to control the devastating epidemic.

Learning that an ambitious immunization program, sponsored by Olafsson, is underway in the jungles of Brazil, Raff secretly travels to that burgeoning South American nation with Hallaby’s experimental anti-viral medication only to find on arrival that evil forces are out to destroy both him and the possible cure.