Driving while drunk destroyed the Soviet spy network in the UK. After being arrested in London in 1971, Oleg Lyalin panicked and offered the names of every Russian spy. The UK government expelled 105 people from the country, and the USSR network in Britain “never recovered”.
Devyatayev was a soviet pilot who was captured by the Nazis in 1944 and managed to steal a German airplane from a heavily guarded Nazi military base. On his return to the USSR his plane was shot at, and was then labeled as a spy because his story was so unbelievable.
A Russian spy infiltrated The Manhattan Project, and drastically sped up Russia’s development of nuclear arms.