In Washington state in 1964, Selma Ježková, a Czech immigrant, has moved to the United States with her son, Gene Ježek. They live a life of poverty as Selma works at a factory with her good friend Kathy, whom she nicknames Cvalda. She rents a trailer home on the property of town policeman Bill Houston and his wife Linda. She is also pursued by the shy but persistent Jeff, who also works at the factory.
Selma has a degenerative eye condition and is losing her vision. She has been saving up to pay for an operation which will prevent her young son from losing his vision. She also takes part in rehearsals for a production of The Sound of Music and accompanies Kathy to the local cinema where together they watch fabulous Hollywood musicals, as Cvalda describes them to her.
In her day-to-day life, Selma slips into daydreams. Soon Jeff and Cvalda begin to realize that Selma can barely see at all. Additionally, Bill reveals to Selma that his materialistic wife Linda spends more than his salary, and the bank is going to take his house. To comfort Bill, Selma reveals her eye condition, hoping that together they can keep each other’s secret. Bill then hides in the corner of Selma’s home, knowing she can’t see him, and watches as she puts some money in her kitchen tin.
The next day, after having broken her machine the night before through careless error, Selma is fired from her job. When she comes home to put her final wages away she finds the tin is empty; she goes next door to report the theft to Bill and Linda, only to hear Linda discussing how Bill has brought home their safe deposit box to count their savings. Knowing that Bill was broke and that the money he is counting must be hers, she confronts him and attempts to take the money back. He draws a gun on her, and in a struggle he is wounded. Linda runs off to tell the police at Bill’s command. Bill then begs Selma to take his life, telling her that this will be the only way she will ever reclaim the money that he stole from her. Selma shoots at him several times, but due to her blindness manages to only maim Bill further. In the end, she performs a coup de grâce with the safe deposit box. Selma slips into a trance and imagines that Bill’s corpse stands up and slow dances with her, urging her to run to freedom. She does, and takes the money to the Institute for the Blind to pay for her son’s operation before the police can take it from her.
Selma is caught and eventually put on trial. It is here that she is pegged as a Communist sympathizer and murderer. Although she tells as much truth about the situation as she can, she refuses to reveal Bill’s secret, saying that she had promised not to. Additionally, when her claim that the reason she did not have any money was because she had been sending it to her father in Czechoslovakia is proven false, she is convicted and given the death penalty. Cvalda and Jeff eventually put the pieces of the puzzle together and get back Selma’s money, using it instead to pay for a trial lawyer who can free her. Selma becomes furious and refuses the lawyer, opting to face the death penalty rather than let her son go blind, but she is deeply distraught as she awaits her death. Although a sympathetic female prison guard named Brenda tries to comfort her, the other state officials are eager to see her executed. Brenda encourages Selma to walk. On the gallows, she becomes terrified, so that she must be strapped to a collapse board. Her hysteria when the hood is placed over her face delays the execution. Selma begins crying hysterically and Brenda cries with her, but Cvalda rushes to inform her that the operation was successful and that Gene will see. Relieved, Selma sings the final song on the gallows with no musical accompaniment, although she is hanged before she finishes.