F.B.I. agents David Blair and Thelma Avery are assigned to search for Professor Weiss, who had mysteriously disappeared after discovering an antidote for atomic radiation.

Professor Freeman is an important English scientist that is investigating a method to treat cancer. His daughter is killed in the swimming pool of a hotel in Beirut. The case is confidential so that the mission is entrusted to the Special Agent Mikel Brown.

Three enemy agents lead a government security man on a perilous trail as the hunter becomes the hunted.

1963 film by Ugo Gregoretti