Raibahadur Satpal Singh (Nazir Husain) is killed cold-blooded in a remote village. He is survived by his twin daughters Rekha & Rashmi (both played by Rekha). Rekha manages their business with the help of their chief estate manager Deewan (A. K. Hangal) along with his son and factory manager Kishore (Danny). Rashmi and Kishore are in love with each other which displeases Rekha, who sends Rashmi abroad to attend a painting course. On the other hand, Rekha too is disinterested about her marriage. Meanwhile, driving through their estate, Rekha's car breaks down and is helped by Prem (Shashi Kapoor), with a golden hand for such machines. After a few meets, both fall in love with each other. After a few days, Rekha announces her engagement with Prem to the surprise of everyone around. She also wills to assign the entire estate to Rashmi before engagement. During the engagement, when Rekha's Police Inspector friend Vikas shows up to wish the couple for the occasion, Prem is suspiciously found missing. The next evening, the couple go out to spend private time on a house-boat anchored in a lake on their estate. Later in the stormy night, Rekha finds Prem missing from the boat and starts looking for him. While searching, someone pushes her in the lake, but not before Rekha glimpses the shadow of this person. Everyone at the estate is surprised with the news of Rekha's death. Meanwhile, she survives and reaches the house of her friend Pinky (Aruna Irani). Once there, Rekha learns about Rashmi's arrival for Rekha' funeral, and both plan to investigate the incident. On the other hand, Kishore, Prem and the Police too start their investigation separately to unmask the killer. Meanwhile, when Rashmi (Rekha disguised) meets him, Prem discloses the intense love for Rekha. She finds quite a few on her suspect list. Kishore wills to go to any extent to marry Rashmi. Prem for his suspicious movements. The staff at their estate, like the cook (Jagdeep), house keeper Ambu (Lalita Pawar) et al. The story progresses and after a few thrilling sequences, the murderer is revealed in the climax.