The first mission in the Soviet campaign occurs during the Battle of Stalingrad on September 18, 1942. Corporal Alexei Ivanovich Voronin, a young volunteer, and his fellow recruits are sent across the Volga River, many of whom are subsequently killed when the Luftwaffe launch an attack. Once across, Voronin is given a small number of bullets, which he gives to a fellow soldier so he can cover an officer calling in an artillery strike that forces the Germans back. The second mission begins in Red Square with Soviet officers killing soldiers who retreat (see Joseph Stalin's Order No. 227—"Not one step back!") Some say the opening of the campaign is based on Enemy at the Gates. Voronin gets his hands on a rifle and kills several German officers, disrupting the German offense long enough for Soviet artillery to destroy their tanks. In the next mission, Voronin links up with his surviving allies in a train station and must guide them to Major Zubov of the 13th Guards Rifle Division. For his actions, Voronin is promoted to Junior Sergeant. The fourth mission, on November 9, has Voronin moving through the sewers to rendezvous with a unit tasked with retaking an apartment building in German hands. The following fifth mission has Voronin join the unit, led by Sergeant Pavlov, as they prepare to attack the building (see Pavlov's House). Voronin acts as a counter-sniper while another soldier draws the fire of the snipers in the building; the unit assaults the building, clears it of Germans and defends it from a German counterattack until reinforcements arrive.