It is October 1941. Some 20,000 heavily armed Wehrmacht soldiers advance on Kalinin (now Tver') en route to Moscow. A small garrison of 2000 Soviet soldiers without tanks or artillery but aided by a people's militia prepare to defend the provincial city, while saboteurs plot to undermine these efforts, sow fear and confusion, or persuade the inhabitants to support the enemy. A voice-over darkly intones that each inhabitant must make a choice: flee the city or stay and defend it.