Amitabh plays Kumar Sen, an artist by profession. He is in love with Asha (Yogeeta Bali). Asha wins a trip to Ooty in a dance competition, and falls in love with a wealthy tea plantation owner, Rajesh (Navin Nischol). When Kumar finds out, he goes to Asha's uncle, Ashok Verma (Om Prakash), and demands Asha's hand in marriage. When Ashok refuses, Kumar kills him. The manner in which Kumar plans and executes the murder is regarded as an immensely brilliant and engaging sequence. Kumar boards and exits, various modes of transportation to avoid any possibilities of suspicion and finally frames Rajesh in the case and tries to win Asha's love. Asha, still in love with Rajesh, promises Kumar to stay with him forever, if he can get Rajesh released from his death sentence. Unable to digest that, Kumar understands that Rajesh will always remain Asha's love. He writes down his confession, gives it to Rajesh, and commits suicide.
The sequence of Kumar's use of various modes of transportation was an inspiration for the 2007 Bollywood film Johnny Gaddaar where it is shown that the film's protagonist watches Parwana film and does the same to avoid suspicion.