Declassified government documents reflect that Lee stole battle plans, which led to the fall of Norway to Nazi Germany in 1940.
German commander General Eduard Dietl, who was holding the Norwegian port of Narvik, was reportedly considering a withdrawal, but the disclosure of these details meant his forces could block the Auchinleck plan.
[4] Lee's existence was discovered by the British in late 1940, when German spies posing as meteorologists were captured by the Royal Navy on an Arctic island.
One spy, Hans von Finckenstein, revealed Lee's identity and the key role that German intelligence believed she had played at Narvik.
Lee disappeared for a period of time and was last spotted by MI5 in 1948 at the Ritz Hotel in Madrid, Spain travelling under a Polish passport.