The film opens in 1936, just before Joseph Stalin's Great Purge. Colonel Sergei Kotov (Nikita Mikhalkov), an Old Bolshevik and decorated hero of the Russian Civil War, is enjoying life in his country dacha. Alongside him is his wife, Maroussia (Ingeborga Dapknait), their daughter, Nadia, and Maroussia's large and eccentric family of Chekhovian aristocrats. The charismatic Kotov, relaxed in his semi-retirement, is held in awe by all who surround him.
Into this idyllic setting walks Mitya (Oleg Menshikov), an ex-nobleman and veteran of the anti-communist White Army. In addition, Mitya was also Maroussia's fiance before his sudden disappearance in 1923. He is joyfully embraced by the family and introduced to Nadia as "Uncle Mitya." However, it soon becomes clear that despite his humorous, friendly nature he has returned with a secret agenda. Mitya now works for the Secret Police, or NKVD, and has arrived to arrest Colonel Kotov for involvement in a non-existent conspiracy.
This is revenge to some extent, as the reason why he left Maroussia was that Kotov forcibly conscripted him into the CHEKA. As a result, Mitya detests Kotov, whom he blames for taking away both Maroussia and his own Orthodox Christian faith. Kotov, however, comments about Mitya's duties in Paris where, posing as a musician, he delivered five White Army generals over to Stalin's death squads. Kotov accuses Mitya of being "a whore" whose loyalty was bought and paid for by the Soviet State. He is certain that Mitya's plans to arrest him are nothing more than a personal vendetta. Citing his enormous popularity and his close relationship with Stalin, Kotov tells Mitya indignantly that the regime will never dare to touch him. Seething with hatred, Mitya vows to repeat these words to him in the Lubyanka prison after he confesses to false charges of espionage, treason, and plotting to murder Stalin. He further adds that, if Kotov will not confess under torture, threats to his wife and daughter should easily do the trick. Enraged, Kotov punches him in the face. As soon as Nadia returns, however, they continue their charade of friendship.
Eventually, however, a black car filled with NKVD agents arrives to arrest the Colonel. Meanwhile, a group of Komsomol children arrives at the dacha to pay tribute to Kotov as a hero of the Revolution and the Civil War. In a deeply ironic moment, Kotov leads them all in an oath of absolute loyalty to Stalin and the Party as Mitya looks on. Moments later, Kotov is summoned to the car.
Even then, the charade continues and Nadia is even allowed to ride part of the way. Thinking nothing is amiss, she kisses her father and Mitya goodbye and walks home. Meanwhile, Kotov's cool, officer's pride remains unshaken. Certain that he can turn the tables on his captors by calling Stalin's private number, he taunts them about the coming destruction of their careers.
Then, however, the NKVD agents find the road blocked by the truck of a peasant who has gotten lost while trying to make a delivery. When Kotov tries to leave the car to give the peasant directions, the NKVD agents batter him to a pulp and shackle his hands. Then, certain that he was sent to rescue Kotov, the NKVD agents shoot the horrified peasant on the spot.
As the car drives past the peasant's corpse, a bloodied Kotov realizes in horror where the decision to arrest him must have come from. With his faith in the Soviet system shattered, Kotov sobs inconsolably. Mitya, who has obviously seen this happen to many other men, remains unmoved. The car drives on until a massive poster of Stalin shields it from view.
A postscript reveals that Colonel Sergei Kotov was convicted of espionage and shot. Maroussia was also arrested and died in the GULAG. Nadia was arrested with her mother, but lived to see all three sentences overturned during the Khrushchev thaw. Having inherited her mother's musical gifts, Nadia Kovota works as a teacher in Kazakhstan. Mitya - as the last scenes of the movie reveal - committed suicide by slashing his wrists.