You might call it the inconvenient truth....
Claudia from Toronto sent me the above name and asked if I had heard of him. I hadn't, but a little Google revealed this. My thanks to the lady from the north.
Igor Sergeyevich Gouzenko (January 13, 1919, Rogachev, Soviet Union – June 28, 1982, Mississauga, Canada) was a cipher clerk for the Soviet Embassy to Canada in Ottawa, Ontario. He defected on September 5, 1945 with 109 documents on Soviet espionage activities in the West.
Gouzenko's defection exposed Joseph Stalin's efforts to steal nuclear secrets, and the then-unknown technique of planting sleeper agents. The "Gouzenko Affair" is often credited as a triggering event of the Cold War. 
What I find fascinating is how poorly he was received..proving that we Yanks and Cannucks are closer than we know.
Gouzenko walked out of the Embassy door carrying with him a briefcase with Soviet code books and deciphering materials. He initially went to the Royal Canadian Mounted Police, but the RCMP officers on duty refused to believe his story. He then went to the Ottawa Journal newspaper, but the paper's night editor was not interested, and suggested he go to the justice ministry, where nobody was on duty. ....
Even once the RCMP expressed interest in Gouzenko, it has been alleged that the Canadian Prime Minister William Lyon Mackenzie King initially wanted nothing to do with him. Even with Gouzenko in hiding and under RCMP protection, King reportedly pushed for a diplomatic solution to avoid upsetting the Soviet Union, still a wartime ally and ostensible friend. Documents reveal that King, then 70 and weary from six years of war leadership, was aghast when Norman Robertson, his undersecretary for external affairs, and his assistant, H. H. Wrong, informed him on the morning of September 6, 1945 that a "terrible thing" had happened. Gouzenko and his wife Svetlana, they told him, had appeared at the office of Justice Minister Louis St. Laurent with documents unmasking Soviet perfidy on Canadian soil. "It was like a bomb on top of everything else", King wrote.
The evidence provided by Gouzenko led to the arrest in Canada of a total of 39 suspects, of which 18 were eventually convicted.... His information also likely helped in the investigation of Julius and Ethel Rosenberg in the U.S. Gouzenko, being a cipher clerk by profession, likely also assisted with the Venona investigation, which probed Soviet codes and which eventually led to the discovery of vital Soviet spies such as Donald Maclean, Guy Burgess, Kim Philby, Anthony Blunt, and John Cairncross (the so-called Cambridge Five), as well as Alan Nunn May.
A movie, "The Iron Curtain" was made in 1948. I am sure if it were made today Igor Gouzenko would be the villain.
That says much about our current cultural affairs.