Russian Empress Catherine the Great faces challenges to her throne on all sides.

A victorious Potemkin returns from war; a Cossack stirs discontent among the countryside peasants.

Catherine and Potemkin experience growing pains in their relationship, as Potemkin's push for expansion puts him at odds with Panin.

Pressure from foreign powers leads to a bitter argument between Catherine and an ailing Potemkin; Catherine works to change the line of succession as her reign draws to an end.