Kathiresan is the son of Parvathi, a maid at the Panchayat president's (O.A.K.Thevar) house and her husband (S.A.Ashokan) is a cattle herder. In a fight about gambling debts, his father kills a man and runs away with the police on his tail. He is later found and sent to jail for life imprisonment. Ravi, the son of Panchayat president of Salaiyur village in Chengapattu District, is Kathiresan's classmate. Ravi bullies Kathiresan and is not good in studies, while Kathiresan excels in it. Being jealous of this, the Panchayat president wants Kathiresan to quite studies and be a cattle herder. But Parvathi is intent on Kathiresan being educated and relocates to Madras. She becomes a maid in a school and a worker in a rice mill. With great difficulty Kathiresan studies well and get admitted to a college. To help pay his fees, he works as a Cycle Rickshaw puller on the side.

Ravi, who grew up to be a playboy, is enrolled in the same college as Kathiresan. Kathiresan and Shanthi, who is the college-going daughter of Judge Satyamurthy, fall in love with each other. He passes his M.A in distinction and gets a job as a lecturer in the same college while preparing for his IAS entrance exams, which Ravi dislikes. Ravi finally gets dismissed from college due to his bad behavior. In revenge, he kills a student, Mani, and frames it on Kathiresan.

Ravi is ultimately found responsible for the murder and sent to the same jail as Kathiresan's father for life imprisonment. Kathiresan becomes an IAS officer and ends up coming to the same jail for inspection.

Kathiresan's father is released from jail and learns that his son is now an IAS officer. Ravi's father tries to assassinate Kathiresan with a bomb at a village function but is saved by Kathiresan. They are all reunited.

The comedy track is provided by Ramu (a rickshaw puller turned car driver) and his lover.