The play begins with Mari having a new telephone installed in her apartment where she lives with her daughter LV (short for Little Voice). She is having it put in so that her new boyfriend, Ray Say can call her. One of the men installing the telephone is Billy who leaves his hammer behind. Mari leaves and Billy comes back for his hammer and is greeted by LV.
Ray arrives at the apartment and Mari is trying to make love to him, but he hears LV singing covers of songs in her bedroom and he is mesmerized by her voice. He believes she is a star and wants to sign her as he is a low-level talent manager (he manages mostly strippers). He brings Mr. Boo, a club owner over to the apartment to hear her sing. LV is very shy and won't do so, but thinking that she is alone upstairs in her room begins to sing and Mr. Boo overhears it and gives her a time slot to perform at the club.
LV goes onstage but only sings when the lights are turned off as she gets terrible stage fright. Ray wants to help her perfect her act, but LV no longer wants to do it. He convinces her to try again, one last time in order to sing as a tribute to her dead father who introduced her to all of the musical artists she loves. This time she is dynamite and the crowd loves her. Ray and Mr. Boo book LV to sing night after night and she is run down by this. Billy has begun coming by her apartment. He comes to her window in a cherry picker from the truck of the phone company. They pair begin to get closer and he tells her of his love for lights and lighting design.
After having gone on stage week after week, LV has decided to stop performing and Ray goes to her to demand her to go on stage. She suddenly begins having all of the impressions she knows bursting out of her and she even pushes Ray down with great strength. He then leaves her never to return after telling Mari that he doesn't want anything to do with her either, that she's washed up and he has other women. Ray slams the door on his way out and the iron falls off the ironing board and starts a fire that burns the apartment.
The fire has been put out and Mari enters and finds LV's records which she destroys. She hates her daughter as she believes she ruined her chance to marry Ray. LV and Billy appear in the apartment, she is looking for her records and finds them shattered by her mother. Mari screams at LV telling her she is worthless until LV grabs a piece of broken record and holds it to her mother's throat telling her all that has been pent up within her for years about how Mari caused her father's death and hurt her.
Mari is now gone and Billy has come up outside on the cherry picker and begins to show her the lights he's worked up for LV. The room is transformed and Billy asks LV to sing her own song, for herself and she does as the room is transformed into a light show and LV is seemingly lifted off of the ground, she elevates as she sings her heart out.
