Shekhar's (Raj Kapoor) maternal grandmother Nani (Lalita Pawar) is a very loving person, and loves Shekhar dearly as a mother. She is also very religious and firm in her beliefs. She believes that every man must have a male heir to carry on the family's name.

Therefore, she will only permit Shekhar to marry a woman who will bear him a son. Shekhar presents his Nani with Sunita (Waheeda Rehman), the girl he plans to marry. Nani finds out that Sunita cannot bear any children and disapproves of her. Shekar and Sunita marry anyway, and to pacify Nani, pretend that a friend's son is their's.

But for how long will the shrewd Nani allow the wool to be pulled over her eyes?