During the 18th century, German noblewoman Sophia Frederica, who would later become Catherine the Great, travels to Moscow to marry the dimwitted Grand Duke Peter, the heir to the Russian throne. Their arranged marriage proves to be loveless, and Catherine takes many lovers, including the handsome Count Alexei, and bears a son. When the unstable Peter eventually ascends to the throne, Catherine plots to oust him from power.

An ambitious New York socialite plans an extravagant dinner party as her businessman husband, Oliver, contends with financial woes, causing a lot of tension between the couple. Meanwhile, their high-society friends and associates, including the gruff Dan Packard and his sultry spouse, Kitty, contend with their own entanglements, leading to revelations at the much-anticipated dinner.