Irena (Maria Chwalibog) bears one burden each day as she delivers the mail and several others when she goes home to continuing penury after her divorce from an alcoholic husband. She also has the chore of caring for a dying relative, accomplished partly out of compassion and partly on the hope that she will inherit a little cash when the woman dies.
Her son is the only bright spot in her existence, an existence they spend together in an unfurnished, rundown apartment with no running water and the noise of the trains traveling along the nearby track.
Then one day she meets Jacek (Boguslaw Linda), an equally lonely bachelor, as she is delivering him his disability pension -- he is lame from a mining accident. It was hardly a planned occurrence.
Irena faints as she hands the surprised Jacek his envelope, and the two kindred spirits have a shared understanding that grows when they continue to see each other. Irena becomes frustrated at times with her son, who has a tendency to get into trouble, and that situation gets worse instead of better.
Then her boss tells her that her mail route may be taken away from her, and when her dying relative finally succumbs, Irena is not only left without an inheritance, but faced with a funeral bill.
In desperation she steals the pensioners' money that she is supposed to deliver, puts her son in a boarding home, buys an old car to make a dash for West Berlin and gets ready to escape her home, her life, and her poverty. At this point, the story has shifted gears as it heads into a narrative warp that signals a surprise ending.