Indian Air Force officer Arun Varma sings "Mere Sapno Ki Rani" in an open jeep winding along Darjeeling, West Bengal's hills with his co-pilot Madan. At the same time, Vandana, the daughter of Dr Gopal Tripathi casts glances from a train window, which Arun notices. Upon multiple meetings over a few days, they fall in love and get engaged. Excitedly, they secretly wed in a temple without rituals, only exchanging garlands, with God as the only witness, however they plan to get married in a formal ceremony in front of their relatives and friends. As it rains heavily, they take refuge in a shelter with a flickering fire, leading to them becoming intimate. Arun tells her not to be ashamed of their intimacy as they have accepted each other in every way in front of god. He promises to be back in some time to get married.

Within days, Arun dies in a plane crash. Vandana discovers that she is pregnant. Arun's family is unable to accept her as a daughter-in-law. Her father also dies, leaving her destitute. Vandana's son is born and named Suraj. She puts him up for adoption hoping to adopt him the next day legally but she is forced to let a childless couple adopt him. Determined to be a part of his life, she accepts the role of being his nanny. One day, her employer's brother-in-law, finding her alone in the house, attempts to molest her but Suraj rescues her by stabbing him to death and runs away. When the police arrive, Vandana takes the blame for the murder and is arrested.

Years later when Vandana is released, the jailor takes her to his home and introduces her to his daughter Renu. Vandana soon meets Renu's love, Suraj. He is the image of his father and a pilot too. He has the sensation of having seen Vandana before but his memories are fleeting. Anxious that the true story of his parents may cause him pain, Vandana tries to hide away.

Suraj is injured in an air crash like his father but survives. While he is recuperating in the hospital, Vandana meets Madan. He knows the truth of Arun and Vandana's romance and is anxious to tell Suraj all but Vandana fears the consequences. One day idly looking through papers in the room while waiting for Vandana, Suraj finds Arun's photo. A sudden realisation that Arun and Vandana are his true parents becomes clear. He recognizes his mother's sacrifices and celebrates her strength and courage.