The Intelligence service traces its roots to Revolutionary War hero Nathan Hale.
Biplanes and spy satellites are among the aerial methods of gathering secret information.
The history of how the Federal Bureau of Investigation monitors interstate crime, including the G-man era and the communist hunting in the 1950s.
The city of Berlin has always been a hotbed of espionage.
Britain's counter-espionage service proves highly effective in both World Wars.
How spy planes, first employed by Gen. Pershing in his Mexican campaign in 1916, were used in World War II and for the protection of the free world.
The Russian Bolshevik organization that took control as Lenin's secret police.
How German intelligence spread across the globe, throughout occupied and neutral Europe and in the United States.
Israel's Mossad intelligence service allows nothing to stand in its way.
Countries try to break down enemy security.
The CIA is a global agency for collecting and evaluating intelligence through covert action.
The Soviet Union's chief military intelligence group produces a network of spies operating worldwide.
The Japanese intelligence network, from the build-up to Pearl Harbor and beyond.
The KGB is responsible for Soviet state security from 1954 to 1991.
A look at the role intelligence-collection ships played in all the major conflicts in the 20th century.
Naval intelligence plays an active role during the Cold War.
The history of French intelligence services, which was active during World War I and colonial conflicts.
Britain's Secret Intelligence Service breaks the Enigma code.
America's Office of Strategic Services is the precursor of the CIA.
British secret agents fight the Nazis behind the lines.
Mata Hari; Sidney Reilly; Lawrence of Arabia; Cicero; Lonsdale; the Lucy Spy Ring.