This bold social drama follows the life of Kokila (Shoba), a medical college student lives with her father, an engineer and her mother in a home in Madras. A house maid (Roja Ramani) who is very close to the family also lives with them. As Kokila's father travels a lot and his wife suffering from health problems, they decide to keep a paying guest.
Vijayakumar (Kamal Haasan), a bank executive comes and lives in the household as a paying guest. Kokila and Vijayakumar fall in love and plan to get married with the consent of her parents. In the meanwhile, suddenly one night Vijayakumar and the house maid are alone in the home. They both end up making love, and Kokila after her return remains unaware about this incident, though the maid is well aware of Kokila's affair with Vijay.
Vijay, however, forgets the maid and continues to live with his normal love for Kokila. Suddenly, one day while Kokila is away on a college tour, Vijay gets to know that the maid is pregnant. Sathya suggests the maid that the child be aborted. The dejected maid leaves the house. When Kokila returns from the tour realise both Vijay and the maid missing.
She is informed by her mother that Vijay has vacated the room, and makes several unsuccessful attempts to find the whereabouts of Vijay. After a few days, Kokila meets Vijay accidentally, in a village where she is posted as a doctor. At the point in time, she gets to know that Vijay and her maid got married and have a child named "Kokila".