1965: Spies Martin and Felicitas investigate the secret cooperation of West-German and South-African politicians in building nuclear and biochemical weapons. When a German scientist is contaminated and escapes he is pursued by killers.

Machholz desperately tries to locate the evidence he had previously sent to Frankfurt. Born's killers track him down, but Martin saves his life. Wilson wants to recruit Felicitas and Dr. Clemens for CIA activities in South Africa.

Born takes Mrs. Machholz to South Africa, hoping she will help expose the whistle blower in the weapons plant. Martin gets support from CIA agent Wilson, infiltrates the secret brotherhood, and identifies a German politician as a member.