Robert Hanssen is a former FBI agent who was convicted of spying against the U.S., for the Russian intelligence agencies. Hanssen reportedly sold countless classified documents containing U.S. nuclear and military strategies. He pleaded guilty to avoid the death penalty. He eventually received 15 life sentences, without parole.
Aldrich Ames is a former CIA officer who later became a KGB double agent. He was convicted of spying and is currently serving a life sentence. He allegedly worked as a Soviet spy and revealed classified CIA data. He inspired the 1998 film Aldrich Ames: Traitor Within.