Kabhi Kabhie (1976)
This Yash Chopra film saw Amitabh play Amit Malhotra, well and truly in love with Rakhi. But familial pressures give rise to circumstances wherein she is married off to Shashi Kapoor.
Bachchan vanishes in a huff, reappearing to marry Waheeda Rehman -- if only out of spite. He later realises that she was an unwed mother, before he came along. There is severe emotional friction between Amitabh, Waheeda and the two couples who interact frequently. The film explores this fragile dynamic.
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