With the Soviet Union already stretched thin fighting the German advance, an alien landing force touches down in Siberia — stabbing socialism in the back from a direction no one was watching. Stalin's response is characteristically inflexible: it does not matter who the enemy is, only that they must be destroyed. Tank brigades and rifle companies charge the alien positions, Communists and Komsomol members at the front, as advanced Martian technology meets the sheer morale — and the personal intervention — of Comrade Stalin himself.