Sudhakar is a poor man desperately looking for work. One day he has a skirmish with Radhika, a rich woman and only daughter of a businessman Selladurai, in a telephone booth. Radhika finds out that Sudhakar is searching for a job from his diary that he leaves at the booth. She employs him in her father's firm as a manager and soon they mutually fall in love. Radhika's class-conscious father initially opposes but later reluctantly agrees to have them married. However things take a turn when his business friend Sivaraman, to whom he owes a lot of favours, visits him and reminds him of his old promise to get Radhika married to Sivaraman's son Vijayan. And soon after Sudhakar goes missing with five lakhs of the office cash on his way to Bombay and is presumed to have absconded. Radhika is heart-broken and her father takes her to Sivaraman's estate in Ooty to relax for a while.

In Ooty, Radhika and her father are introduced to Vijayan who shockingly seems to be a severely despondent alcoholic. He is often seen standing near the shore of the river listening to his tape recorder playing a lone melodious song, sung by a woman. After a few days in the estate and several interactions, Vijayan and Radhika get acquainted and friendly with each other and he opens up about his erstwhile lover Rathi. Vijayan had fallen in love with the beautiful Rathi at first sight and pursues her relentlessly till she finally reciprocates. Rathi often playfully cheats Vijayan about not knowing stuff like horse riding and car driving when she actually could. And on an April Fool's Day when she claims she doesn't know how to swim, Vijayan thinks she's fooling him again and playfully pushes her into the river but to his horror she drowns and dies. The incident left Vijayan as a suicidal wreck who carries poison in his coat but doesn't consume it just for his father's sake. Rather he has chosen the slow poison of alcohol. When Vijayan learns Radhika too has a past forlorn love affair, he feels closer to her since they both seem to be in the same boat.

As days move on, Vijayan and Radhika get closer to each other and eventually agree to get married, much to the delight of their fathers but then on an eventful day Radhika encounters Sudhakar working as a gardener in the estate. Radhika angrily admonishes him for having deserted her and walks away but Vijayan is determined to find out the truth. It turns out that Sudhakar was coerced and forced to decamp by Radhika's father himself so he could get her married to Vijayan. On the day of their supposed marriage, Vijayan gets Radhika united with Sudhakar and they leave town together. Later, Vijayan who had promised to Radhika to give up alcohol, instead consumes the poison he carried in his pocket and walks into the river that had once consumed his beloved Rathi. Before dying Vijayan makes a statement to God, "They say love is blind, but You have been blind to my love, so I am leaving my glasses for You".