On one of the October nights at the ball, gymnasium pupils and officers scoff at the love of Kuzma Zakharkin, the “cook's son”, to Lena, the daughter of the manufacturer. Cannon volley interrupts the fun. In the city begins the Moscow armed uprising of workers.

At the center of the fate of two families is the capitalist Leontyev and the worker Zakharkin, whose sons became the organizers and participants of this uprising.