Zameer (1975)
Many years before Baghban, Ravi Chopra made his directorial debut with this bold film. Amitabh plays Badal, an impostor claiming to be the once-kidnapped son of Maharaj Singh (Shammi Kapoor).
He then proceeds to fall in love with the heiress Sunita (Saira Banu) -- who is, in implied effect, his sister. While his being an impostor is clear to the viewer from the beginning, thoughts of incest assault Sunita's ailing mother (Indrani Mukherjee) as the lovers begin to step gradually into the open.
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