Manian (Delhi Ganesh), a rickshaw puller, lives with his wife Valliamma (Tambaram Lalitha), two daughters, and five sons in abject poverty. He is the sole breadwinner and earns around Rs. 7/- per day, of which he spends Rs. 4/- for liquor and gives the balance to his wife. His wife struggles to make ends meet with that paltry income. Her friend Rakkamma (S.N. Parvathy), a food hawker in the locality, is the only support to the family.
Their son Krishna, who is educated, elopes with a girl and lives separately and does not support the family. Manian's daughter Kuppama (Shobha) along with her friend Chellamma (Sathya) starts picking rags on the streets and contributes to the family by earning Rs. 2/- per day. People try to take advantage of her poverty but she never relents. Lorry driver Rangan (Vijayan), who is good-hearted, befriends Kuppama and helps her whenever she is in need. Slowly, both of them become very close and their friendship develops into an intimate relationship. On learning that her daughter has had a physical relationship with Rangan, her mother commits suicide to avoid disgrace. When Kuppama comes to know that Rangan is already married, she gets shocked as she had assumed him to be unmarried. She maintains complete secrecy about him and does not inform anyone about Rangan as she does not wish to disturb his family in any way. Kuppama learns that she is pregnant; despite advice from neighbors, she does not terminate it. Rangan tries to support her but she avoids him completely; instead, she cooks up a story for her relatives that her lover died in an accident.
However, during the advanced stages of pregnancy, Kuppama desires to meet Rangan, but he has moved out of the original place after Kuppama rejected his support. Rangan's wife, coming to know about their relationship, empathizes with Kuppama and advises Rangan to bring her home. When Rangan comes to take her, Kuppama, who was coming to meet Rangan, develops labor pains, and dies after delivering a child. Rangan and his wife get shocked when they see a dead body with a just born baby on the road. The child is brought up by Rangan and his wife.
[from the book Pride of Tamil Cinema: 1931 to 2013 by G Dhananjayan, Blue Ocean Publishers 2014]