After World War II,  what came next was countries hiring agents to spy on one another in hopes of discovering and getting information about plans, tactics, weapons, and whatever intelligence reports they could get. Whether to get ahead of the other nations that posed a threat or just for the peace of mind that they won’t be surprised by a nuke one day, espionage agents became their countries’ secret weapons.

Double agents became a thing, too. Those spies pretended to work against the nation they were really loyal to, so they could get the juiciest of information, although some just betrayed their country. Here are the six who did:

Aldrich Ames

Aldrich Ames
Aldrich Hazen Ames; former CIA officer convicted of espionage. (Source: staff, Federal Bureau of Investigation/Wikimedia)

Aldrich Hazen Ames was one of the most infamous CIA traitors in the country. Nevertheless, he began his journey in the CIA. He had no plans of joining the organization, but after getting an outstanding GS-7 rating and high performance during his tests, he was accepted into the Career Trainee Program. He was assigned to various projects, but it was in his 1976 stint in New York that he started interacting with Soviet assets. During this mission, he received praises from the organization and even got promoted to one of the highest-ranking officers in his pay grade.

As he became increasingly involved in Russian intelligence in 1985, Ames was one of the officers assigned to assess Soviet embassy officials. CIA was looking to find potential intelligence assets at the time when the Russian offered him $50,000 for information.

Ames reportedly believed he only gave them “essentially valueless” information that would help him get closer to them, but he tried to play the double-agent game. He was enticed by the Russians, and it was easy money for him. Even when he was assigned to Washington, DC, in 1989, he continued what would now be known as “KGB drops.” Worse, he even let his wife (also part of the CIA) in his stint.

Ames thought he would evade being tracked by “outing” the Russians paying him to the US government. Then, in May 1993, the FBI opened a 10-month investigation where they found surmountable evidence of espionage and treason.

On Apr. 28, 1994, Ames and his wife pleaded guilty.

Donny Walker (John Anthony Walker)

John Anthony Walker Jr.
In 1985, dubbed by the press as the “Year of the Spy,” former U.S. Navy warrant officer John Anthony Walker, Jr. was arrested for selling U.S. secrets to the Soviet Union.  (Source: Federal Bureau of Investigation (FBI)/Flickr)

John “Donny” A. Walker Jr. was a former Navy officer who created a spy ring, stealing military documents and selling them to the Soviets. He is still known as one of the most damaging spies in American History.