In the opening sequence, jailed former labor leader Nataraj (M. G. Ramachandran) is telling his cellmates about the suffering his family endured as a result of uncle Ponnambalam (K. Sarangapani) betraying his fellow Indians in order to help the British. Nataraj tells of how Ponnambalam murdered his father, swindled his mother of her meager savings and forced her sister Leela (P. K. Saraswathi) into marriage. Nataraj hunts down and kills his uncle, which lands him in jail to tell his story.
Circa 1947. Ponnambalam Pillai helps himself to the properties and riches of his brother-in-law Chidambaram Pillai, who is settled in faraway Karachi. Ponnambalam is aided by his sidekick Jambu and the court clerk Muniyandi. When Chidambaram Pillai returns home and starts questioning Ponnambalam, he is killed.
In the aftermath of India Pakistan partition, Chidambaram Pillai’s family manages to escape from the strife torn Karachi. His wife, son Natarajan and daughter Leela reach their hometown, only to find Chidambaram Pillai dead. They are driven away by the heartless Ponnambalam. An honest youth Balu, who is moved by their plight and offers them shelter in his house and falls in love with Leela. Natarajan who took pity for Vallikannu, who had been a victim of Ponnambalam’s lust, soon turns to love.
Jambu gets Natarajan arrested on trumped up charges, and succeeds in getting Leela married to Ponnambalam. Leela pretends to be haunted by a ghost, and manages to postpone consummating the coerced marriage. But Jambu sees through her pretences and makes bold to molest her. Balu rushes to save Leela from her ordeal, but when he reaches her house, he finds Leela torn and bruised, and Ponnambalam is lying dead. Balu is charged with the murder and arrested.