Plot: The War of the Century: When Hitler Fought Stalin, is a BBC documentary film series that examines Adolf Hitler's invasion of the Soviet Union in 1941 and the no-holds-barred war on both sides. It not only examines the war but also the terror inside the Soviet Union at the time due to the paranoia of Joseph Stalin - the revenge atrocities, the Great Purge of army officers, the near-lunacy orders, and the paranoia of being upstaged by others, especially Marshal Zhukov