Kadal Meengal (1981)

Selvanayakam a.k.a. Selvam (Kamal Haasan) is a poor but hard-working fisherman who is in love with Bhagyam (Sujatha) from the same fishing hamlet. After a tiff with the locals, Selvam moves to a neighbouring village for fishing and is feared dead during a cyclone. Selvam returns alive after a while and unable to find Bhagyam, marries another woman. Bhagyam has borne his child but lives in isolation away from the life of Selvam who has grown to be a rich businessman. After several years, Bhagyam's son Rajan (the younger Kamal Haasan) finds out about his father whom he despises for having deserted his mother. He vengefully joins his father's rivals and enters into a long confrontation with his father in business and in personal life as well. Nisha (Swapna), is Rajan's love interest while Ambika plays his step-sister's role.