FBI agent Ed Renard investigates the pre-War espionage activities of the German-American Bund.

The US Government tries to track down embedded Nazi agents in the States.

Canadian Mountie Steve Wagner captures a German Luftwaffe officer on a spy mission, who later escapes from the prison camp. To catch the spy ring, the Mounties employ a ruse so that the spies, believing Steve to be sympathetic, enlist him in their plans.

In preparation for Operation Overlord, the Allied invasion of Nazi occupied territory, the 'overlords' were the few Allied agents who knew the details of the operation. When one them is captured by the Germans, a double agent must infiltrate occupied Paris, with the help of a high level German officer and the French Resistance.

A thought provoking documentary feature film providing a comprehensive exploration of the evolution of signals intelligence over the past century. Whether you're intrigued by the secretive world of intelligence agencies or concerned about the implications of digital surveillance, this film will leave you with a deeper understanding of the role signals intelligence plays in society.