Operation Lemon Aid-- an induced double agent operation-- was conceived, controlled, and concluded as a cooperative counterintelligence effort by the FBI and U.S. Naval Investigative Service (NIS). Two Soviet employees of the UN Secretariat, Valdik Enger and Rudolf Chernyayev, were arrested for accepting classified information from Navy Lieutenant Commander Art Lindberg, who was acting as a double agent for the United States. In 1978, Enger and Chernyayev were convicted of espionage and sentenced to 50 years in prison.
(From: https://www.cia.gov/library/readingroom/docs/CIA-RDP02T06251R000600010001-7.pdf)
LCDR Art Lindberg-- Acted as a double agent for the United States in the counterintelligence operation known as Operation Lemon Aid. In August 1977, Lindberg took a trip on a Soviet cruise ship, and upon return to New York, he passed a note to Soviet officers containing an offer to sell information. He was later contacted with instructions on what type of information to get and locations for drop sites. Enger and Chernyayev, along with a third Soviet officer, were apprehended at the drop zone.
(From: http://www.dhra.mil/PERSEREC/Espionage-Cases/navy1/)
This video takes you behind the scenes of one of the most daring undercover operations in history-- Operation Lemon Aid.
International Spy Museum Historian Vince Houghton sat down with former US Navy officer and double agent Art Lindberg to discuss his career and the sting operation that snared multiple Soviet spies.