Ilamai Oonjaladukirathu

Prabhu is an orphan raised by Murali's mother and serves as the general manager of Murali's marketing agency in Madras. Murali treats Prabhu as a brother and relies on him for important business decisions. Prabhu secretly loves Padma, a college student who attracts him.

Padma is a college student who becomes the object of Murali's advances. She is the only woman who rejects him, setting the stage for the complex relationships among the trio. Prabhu remains secretly in love with Padma.

Jayanthi, a young widow who works at Murali's office, is aware of Prabhu's feelings for Padma and is drawn to him. During a film screening, her attraction surfaces and the moment is shared in private in Murali's car, creating a guilty tension among them.

A disturbed Jayanthi takes leave to return to her village, with Padma accompanying her. Prabhu leaves Madras on an official tour, setting the stage for later confrontations.

Prabhu lands in Jayanthi's village to surprise Padma. Padma has gone to attend a wedding in a nearby village, and Jayanthi convinces him to stay overnight so he can meet Padma the next day.

In the night, Jayanthi arouses Prabhu and they make love. Prabhu, overwhelmed by guilt, writes a letter of apology and leaves. Padma returns to Madras and begins distancing herself from Prabhu.

Murali continues to pursue Padma; when she falls, he saves her and gets her admitted to a hospital, impressing her father. He informs Prabhu about his feelings for Padma, but Prabhu remains silent. He then accompanies Murali's mother to formally propose Murali's marriage with Padma.

Padma's father accepts the proposal, while Padma remains silent. When Prabhu confronts her, she reveals that she had read his letter to Jayanthi, who is carrying his child.

Shocked by the revelations, Prabhu leaves Madras without informing Murali and his mother. Later, Jayanthi writes to Prabhu informing him of her pregnancy.

Prabhu travels to Bangalore to settle with Jayanthi and ties a thaali around her neck before she dies, giving her the dignity of a wife. He relocates to Ooty afterward.

Murali falls ill and his wedding to Padma is postponed. He and Padma go to an estate on holiday, unaware that Prabhu works there. Prabhu meets them and apologises for leaving their home abruptly.

Padma learns that Prabhu married Jayanthi before she died and forgives him, attempting to become close to him again. The past is acknowledged, but tension lingers as their bond remains tested.

Murali confronts Prabhu with Padma nearby and takes them to a cliff. Padma reveals their original love and explains how Jayanthi's interference and Prabhu's act of marrying her safeguarded their honour. Murali forgives them, and he presents Padma to Prabhu before leaving for Madras.