The love affair between a squadron leader and a young woman who is involved with agents and saboteurs from foreign countries leads to the exposure of an entire group of spies.

Professor Algeras becomes the target of foreign agents working for major powers, who use every legitimate and illegitimate means at their disposal to try to get hold of his scientific discovery. The most ruthless and unscrupulous foreign agent, who ultimately traps Algeras, is Milko, who comes from the countries behind the Iron Curtain. It eventually transpires that Milko, who has been brainwashed, was the professor's only son, lost during the communist child abductions.