Aap Ki Kasam 1974

Kamal Bhatnagar is a studious young man from a middle-class family, while Sunita Bhatnagar is a wealthy girl. They meet, a misunderstanding arises but later, it gets cleared up. Sunita and Kamal fall in love and decide to marry. They wed with the consent of their families, and they begin a life that feels grounded in mutual respect and shared hopes.

Kamal also gets a house and a job with the help of his best friend, Mohan. Mohan is kind and jovial, but his own life is unhappy due to a shrewd wife. Taking pity on him, Sunita befriends Mohan. At first, Kamal ignores it, but soon he grows suspicious and fears Sunita might be having an affair with Mohan.

The tension escalates when Mohan throws a party, and Kamal discovers Sunita with Mohan, becoming furious. He questions Sunita, who is unaware of any wrongdoing, and she is disappointed, leaving to her parents’ house. Kamal’s father tries to talk sense into him, but he refuses to listen. Sunita’s mother urges her to reconcile, yet her father forbids her from returning. Mohan pleads for trust, even asking Sunita to tie a rakhi on him to prove innocence, but her father rejects that plan as well. He even sends a divorce notice to Kamal to coax him back, but Kamal suspects a bluff and the divorce proceedings proceed. Sunita is heartbroken and is hospitalized.

One evening Kamal sees a man jump the boundary between his property and Mohan’s. He pursues him and learns the man is Suresh, who confesses to an affair with Mohan’s wife and reveals Mohan’s true innocence. Kamal, remorseful, seeks forgiveness from Mohan, who gladly grants it. He then goes to Sunita’s house and faces shocking news: Sunita’s father has arranged a remarriage for Sunita, despite her reluctance.

Devastated, Kamal leaves his home and wanders the streets as years pass. He becomes an old beggar, returns to his former house which is now occupied by another family, and is assaulted on suspicion of theft. Mohan finds him there, reconciles with him, and brings a letter from Sunita. In the letter, Sunita explains she was pregnant when she left Kamal and remarried for the sake of her daughter, and she wishes for Kamal to attend his daughter’s wedding to bless her. Though hesitant, Mohan convinces him to go.

Kamal attends the wedding, but tragedy strikes as a fire erupts in the hall. He sacrifices himself to save his granddaughter and is mortally wounded. Sunita, shaken, reveals to her daughter that Kamal is her true father. Kamal blesses his granddaughter, dying shortly after, and the wedding has now become a funeral.