Suraj ( Dilip Kumar ) and Jugnu ( Noor Jehan ) study in the same college and fall in love. Jugnu's parents died when she was young, and her fathers friend, whom she calls Chachaji, looks after her college and other expenses. Suraj belongs to a rich family. Jugnu's childhood friend Dilip ( her Chachji's son) wants to marry her. Suraj does not like this, and he together with friends, keeps playing pranks on Dilip. One such prank causes Dilip to get seriously ill. When Dilips father ( Jugnu's Chachaji ) goes to visit him, his friends blame Jugnu for his condition. This makes Chachaji angry and he confronts Jugnu and disowns her. With Chachaji gone, Suraj offers to help Jugnu financially. He asks his father for a raise in his pocket money, to which his father reveals that they are not rich but under heavy debt and the only way that can be paid off is if Suraj marries a rich girl of his parents choice, who would brings lots of cash and jewellery in dowry. Suraj does not agree. Suraj's fathers threatens to commit suicide if he does not marry the girl he has picked for him. This scares Suraj's mother. She doe not want her husband to die. So she has a secret meeting with Jugnu and pleads with her to forget Suraj and not see him again. Jugnu is heart broken , but agrees. Jugnu pretends not to love Suraj anymore. Both are heartbroken, but Suraj responds by becoming wayward and emotionless , while Jugnu falls seriously ill.