Krzysztof Kieslowski's treatment of the ninth commandment, "Thou shalt not covet thy neighbor's house," focuses on the itch we all have for something more, better, or different. Being content with what we have takes patience, perseverance, and gratitude whether we are talking about our relationships, work, or possessions.

Roman (Piotr Machalica), a surgeon, goes to a doctor and learns that he is impotent. Deeply upset, he returns home to his beautiful wife Hanka (Ewa Blaszczyk) of ten years. They have no children. When Roman tells her that his sexual dysfunction is permanent, she responds, "Love is in one's heart not between one's legs." Nevertheless, he tells her she should take a lover.

Unbeknown to Roman, Hanka is already having an affair with Mariusz (Jan Jankowski), a physics student. Increasingly restless, Roman starts spying on his wife by bugging the phone and following her around. Learning that Hanka and her lover meet at her mother's place, he waits outside when he knows they are making love. But Hanka is already planning to break off the affair, even though Mariusz wants to marry her. She believes that her marriage can be saved by adopting a child.

A subplot in this drama deals with Roman's treatment of a young woman with a heart condition; she has a beautiful voice but will be unable to sing very passionate music unless she has her heart fixed. Kieslowski wants us to see the many angles to the health of a heart. How much can it take? In Roman and Hanka's case, a lot. Sex turns out not to be the determining factor in the future of their marriage.

Initially Roman's problem proves to be so devastating that both he and Hanka are unable to be honest emotionally with each other. They lose heart, to put it simply, by coveting something beyond their love relationship. In the end, through several traumatic incidents, Roman and Hanka realize that they must make a fresh commitment to each other. Marriage, you see, is an optimum laboratory for the training of the heart in gentleness, compassion, forgiveness, and personal renewal.