Sundaravadivelu [Vijayan] is a wealthy but cruel villager who runs the local school with an iron grip, siphoning its funds for his own desires. He lives with his chronically ill wife Lakshmi [Ashwini] and their two children: son Raja [Khaja Sharif] and daughter Bhavani [Anju Prabhakar]. Lakshmi’s father Thambusamy [Charu Haasan], a pensioner, also resides in the same village and has loaned Sundaravadivelu money, a debt that is kept active by constant pressure for repayment and a string of insults. Shenbagam [Madhu Malini], Thambusamy’s daughter, falls in love with Prakash [Sundar Raj], a new teacher at the school. Sundaravadivelu does not approve of the match, wanting Shenbagam for himself and even offers to write off the debt if Thambusamy agrees. Thambusamy refuses, and Sundaravadivelu vents his anger on Lakshmi. Thambusamy [Charu Haasan] insists on standing by Shenbagam’s choice, further fueling the tensions in the village.
Bhavani falls sick, and Lakshmi takes her to the recently appointed village health inspector [Sarath Babu]. There, they discover they were neighbors years ago and that he had once sought Lakshmi’s hand in marriage. The health inspector genuinely wants to help, and when Thambusamy contemplates leaving the village because of Sundaravadivelu’s harassment, he offers money to settle the loan. Sundaravadivelu retaliates by accusing Lakshmi of an extramarital affair, and with the backing of the village panchayat, he drives Lakshmi out of the family home, keeping the children with him. The health inspector leaves to avoid further trouble, while Lakshmi seeks shelter with her father. Unable to endure life apart from her children, she dies.
Sundaravadivelu remarries and continues to neglect his kids, who still visit Shenbagam for food and care. Prakash [Sundar Raj] informs Thambusamy that the school management has learned of Sundaravadivelu’s mismanagement and is prepared to act. Shenbagam goes to Sundaravadivelu to request custody so she can care for the children, but he becomes enraged when she rejects his possessive claim and forcibly undresses her, boasting that he is the first to see her nude. His wife witnesses the humiliation and disowns him, and the villagers learn of the act. They corner Sundaravadivelu by the river and demand that he choose his own fate. In a final moment of remorse, he shares a tender moment with his children, then drowns himself in the river.
