Answer
In 1940 and 1941, Richard Sorge, a Soviet spy embedded in Japan, delivered critical intelligence to the Soviet Union regarding Adolf Hitler's plan to invade the Soviet Union. This information proved invaluable, as it allowed the Soviets to prepare and mobilize their forces, resulting in a significant advantage at the onset of the German invasion. Sorge's espionage efforts played a pivotal role in shaping the course of World War II.