Russian Empress Catherine the Great faces challenges to her throne on all sides, as she meets the forthright and bold Lieutenant Grigory Potemkin.

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.

A victorious Potemkin returns from war to find Catherine preoccupied, leading the two to speak candidly about their pasts and future, while a Cossack stirs discontent among peasants in the countryside.

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