The film places the story in Kolkata. As the credits roll, scenes from erstwhile Calcutta are displayed along with the narrator’s (Amitabh Bachchan) introduction of the era. The narration focuses on the night of the marriage of Shekhar and Gayatri Tantiya, a rich industrialist’s daughter. The audience is introduced to Navin Rai as Shekhar’s father while we see Shekhar readying himself for the occasion.
While he is doing so, images of Lalita calling him by his name flash through his mind. Downstairs, musical celebrations begin as Shekhar meets Vasundhara, a widow from his neighbourhood, who is thankful to her son-in-law, Girish (Sanjay Dutt), for supporting their family after the death of her husband, Gurcharan. Lalita, who is present there, playfully confronts Shekhar as to why he is being indifferent to her. Shekhar admonishes her for speaking so in spite of being married.
An angry Shekhar comes back home to play a favourite tune from the past on his piano. The flashback shows a young Shekhar playing Rabindranath Tagore’s tune on his piano while young Lalita and Koel are around. Lalita, with her parents having died in a car accident, lives with Gurcharan’s family with Koel as her cousin whereas Charu is her neighbour. As this scene flashes across Shekhar’s mind, he sings a song full of sadness and loss. As time flies, they grow up to become close friends. The rebellious and musically inclined Shekhar spends his days playing the music of Rabindranath Tagore or Elvis Presley and composing his own songs with Lalita rather than becoming part of his shrewd father’s world of profit and business. Part of this rebellion involves resistance to meeting Gayatri Tantiya, the beautiful but devious daughter of a wealthy industrialist, whom his father would like Shekhar to marry into. Meanwhile, Girish, a steel tycoon from London, makes a dramatic entry into Charu’s house. Girish seems smitten by Lalita while Koel is by Girish. Shekhar is visibly jealous of Lalita’s close friendship with Girish.
One day, a shocked Lalita, who is employed at the Ray’s office, remembers a hotel project from Gurcharan’s ancestral haveli (palatial house). On an earlier occasion, Gurcharan had borrowed money from Navin Ray after putting his haveli on mortgage. She understands that if the money is not repaid in a few months, Navin Ray would take over the property. She immediately thinks of asking Shekhar for monetary help. Unforeseen circumstances prevent this, and Girish, upon realising this, alleviates their problem by making Gurcharan his business partner. Gurcharan repays the debt and the turn of events prompts Shekhar to think why Lalita chose to ask Girish for money instead of him. On one auspicious night, Shekhar and Lalita exchange garlands and consummate their “marriage” unbeknownst to anyone else.
While Shekhar is off to Darjeeling on a business trip, Navin Ray violently thunders at Lalita about the loss of his hotel project, embarrassing and humiliating her. Ray gets a wall built between his and Gurcharan’s house symbolising the end of their association. Gurcharan, unable to digest this, suffers a heart attack. Upon Shekhar’s return, Ray informs him of the ill-health of his mother and Gurcharan and viciously adds a note of Lalita and Girish’s marriage. Shekhar is disgusted to hear of the marriage and in his anger he scowls at Lalita, humiliating her like his father. In the meanwhile, Girish assists the Gurcharan family and takes them to London for the heart treatment. Misunderstandings follow and upon the family’s return from London, Shekhar assumes that Girish and Lalita are married and agrees to marry Gayatri. The film returns to the night of Shekhar’s marriage when Girish hands him the ownership papers of Gurcharan’s haveli. He shocks Shekhar by telling him that he got married to Koel because Lalita denied his marriage proposal. As a conclusion, Shekhar confronts his father and symbolically breaks down the wall separating the two families. He then brings Lalita to his home as his bride much to the delight of his mother.