World War II in Colour 4: Hitler Strikes East

There episode explores the war in Russia.  Hitler had forged an alliance with Stalin, but all along he intended to expand the Nazi empire in this direction.  Stalin had forged the deal, knowing that Russia was ill prepared for an all out war.
Hitler's attack on Russia had three movement, north towards Leningrad, center towards Moscow, and south towards Stalingrad.  The early part of this attack showed the effectiveness of blitzkrieg, as the Russians melted away.  However the attack to the south got bogged down.  All of the attacks were slowed as they had to deal with hundreds of thousands of prisoners.  The tank commanders wanted to move on to follow up their advantage.
Hitler made a crucial error.  As they were driving towards Moscow, and where sure to enter the city in just a few weeks, he diverted his panzers to the south, to follow up gains there.  They surrounded Kiev.  However then several times the tanks were moved back and forth, and only after precious time was lost did they finally refocus on Moscow.  The still advanced, but eventually were stalled by the weather.  It got so cold the tanks wouldn't start, nor would they function properly.
Russia on the mean time used this time to prepare a counterattack.  After Stalin assured through his espionage efforts that Japan was not going to attack Russia in Siberia, he repositioned half a million men from Siberia towards Moscow using the Siberian Railroad.  5 December the Russians counter attacked, with some gains.  Hitler ordered that the Germans go into a defensive mode.  The German generals wanted to fall back to consolidate their lines.  Hitler would not give permission, and replaced his generals.  Thousands of German troops were surrounded.  They could have escaped but were ordered to hold.  A Panzer attack to free them proved unsuccessful.  Consequently 200,000 German troops were surrendered, and marched into Russia.  Only 5000 would ever return to Germany.  
In the south, Hitler became determined to take Stalingrad at all costs.  They actually made significant progress, however again a Russian counter attack would leave them vulnerable to capture and only through a sound rear movements were they able to escape.  This was the end of offensive movements by the Germans in Russia, and from there it was always falling back towards Germany.  Of support for the Russians was a new tank which was just as good as the Panzer, and also their rockets, and finally they were able to manufacture air planes.  Initially the Germans had control of the skies, but that would change.