Catherine the Great falls in love with an army officer who is plotting against her.

In the mid-eighteenth century, the Russian court is thrown into upheaval when outspoken, lusty Catherine the Great quarrels with her latest companion, Variatinsky. Although the scheming Gen. Michael Nicolai Vladimirovich Ronsky wants to install his dimwitted nephew Boris in Variatinsky's post as commander of the palace guard, and thereby gain the ability to overthrow Catherine, the czarina's crafty chancellor, Nicolai Illytch, tries to thwart Ronsky by keeping any newcomers from meeting Catherine until he can introduce her to a French ambassador, Marquis de Fleury. Nicolai hopes the marquis will convince Catherine to make an alliance with France, but his attempt to introduce the marquis to Catherine is forestalled by the sudden appearance of Alexei Chernoff, a lieutenant in the horse guards. The dishevelled Alexei describes how his fealty to his sovereign prompted him to sneak into the palace to tell her about a plot against her life, but Catherine, who already knew of the unsuccessful scheme, is more interested in Alexei's abundant physical appeal. Unaware that Alexei is engaged to her favorite lady-in-waiting, Countess Anna Jaschikoff, Catherine has Alexei installed in Variatinsky's now-empty quarters. Catherine then promotes Alexei to captain and gives him a tight, white uniform, which pleases her when he comes to her chamber that evening to report on the army. Catherine attempts to seduce the lovely but naïve Alexei, who is thrilled by the opportunity to kiss "Mother Russia." When Catherine learns that Nicolai had suggested to Alexei that he return to his camp, she is determined to have Alexei stay, and continues to promote him as the days pass. Realizing what Catherine's plans are for Alexei, Anna coldly congratulates him when he is made the new commander of the palace guards, and chastises him for being a plaything instead of a real soldier. Alexei becomes frustrated by his affair with Catherine, for although he welcomes the opportunity to be with her, he longs to be of more use to his country. While Catherine placates Alexei by allowing him to investigate the status of the country's serfs, Ronsky and his cronies try to win Alexei to their revolutionary cause. One day, Catherine learns about Alexei and Anna's engagement, and when she commands Anna to return home, Anna lashes out and tells the czarina that she is making a fool of herself with the much younger Alexei. Without revealing Anna's name, Catherine tells Alexei about Anna's harsh criticisms and he replies that such a traitor cannot be dealt with leniently. Crushed when Alexei refuses to support her after learning the whole truth, Anna agrees to leave the palace. Alexei then gets drunk with Ronsky, who has arranged for Variatinsky to return and inform the still ignorant Alexei that he is merely one in a string of Catherine's lovers. Feeling used, Alexei confronts the czarina and is heartbroken when she refuses to refute Variatinsky's charges for fear of scandal. Alexei also learns that Catherine does not even read his carefully written edicts, and so decides to cooperate with Ronsky. The chancellor, who eavesdrops on Ronsky and Alexei's conversation, pretends to ally with them, and that night, Alexei enables Ronsky's forces to take over the palace. Alexei assures the terrified Catherine that he made Ronsky promise not to kill her and instead give her to him as his share of the "loot." Catherine pleads with Alexei, promising to make him czar, but he does not capitulate. Her pleas are interrupted by the arrival of Nicolai, who engineered a counter-coup. The chancellor escorts in Ronsky, who has been arrested, and Alexei is also jailed for his part in the failed revolution. Claiming Ronsky as his share of the "loot," Nicolai makes the disgraced general act as his servant while Alexei languishes in captivity because he refuses to apologize to Catherine. Hoping to reunite Anna and Alexei, the chancellor arranges for Catherine finally to meet the smooth-talking Marquis de Fleury. While Fleury heaps praise upon the czarina, Nicolai secures a guarantee of freedom for Alexei from her, then leaves the marquis and Catherine to their new romance.