The film tells, in flashback, the story of Suresh Sinha (Guru Dutt), a famous film director. His marriage to Bina (Veena) is on the rocks because her wealthy family sees film-making as a job lacking in social status. He is also denied access to his daughter Pammi (Naaz) who is sent to a private boarding school in Dehradun.
On a rainy night Sinha meets a woman Shanti (Waheeda Rehman) and gives her his coat. She comes to the film studio to return the coat, unintentionally disrupting the shooting by walking in front of the camera. While reviewing the rushes, Sinha recognises her potential as a star in the making and casts her as Paro in Devdas. Shanti goes on to become an acclaimed star. Shanti and Suresh, two lonely people, come together.
Their liaison is hotly debated in gossip columns and results in Pammi's friends tormenting her in school. Pammi pleads with Shanti to leave Sinha's life and allow her parent’s marriage another chance. Moved by Pammi’s plea Shanti throws away her career and becomes a school teacher in a small village. Pammi decides to live with her father who also fights the case in court against his in laws but is defeated and had to let pammi go with her mother. This and Shanti’s departure drives Suresh to alcohol, a downhill slide in his career and consequent decline in his fortunes. Shanti is forced to return to films since she has a contract with the studio.
Producer of the films agrees to hire him because of Shanti but he refuses due to his ego and refuses to go back. He is unwilling to accept the job that comes as a sop to assuage the wishes of Shanti, who is now a star; so she is unable to help him, as he is too far-gone for redemption. In the final scene, Sinha, remembering his glorious past, dies in the empty film studio in the director's chair, a lonely and forgotten man.