In an effort to expose the mafia resident, the criminal investigation inspector infiltrates the criminal environment and finds out who is hiding under the guise of one of his bosses.

Katerina Izmailova, a beautiful and uneducated merchant's wife, feels lonely and bored somewhere in the Russian provinces while her older husband is often away. Years go by in her childless marriage, without an outlet for her youthful energy, resulting in constant idleness and frustration. Along comes Sergei, an unscrupulous young worker who is happy to improve his lot by seducing Katerina as he has done with others before. Katerina falls for Sergei, and this love quickly becomes her only reason for living, turning to destructive passion and ultimately to tragedy for many.