Mamta lives a poor lifestyle with her husband, Dinu, and two sons, Mohan, and Sohan. When Ram Lal, the wealthy Zamindar, Kanta Prasad Gupta's Munim, comes to them to take Sohan to Mrs. Sharda Gupta for ten days, they reluctantly permit him to do so. After 10 days, Gupta himself approaches them and begs them to let his wife keep Sohan for life. They tearfully agree. Then Mohan gets into trouble, and Dinu scolds him, only to find out that Mohan has run away from home. A search proves futile, and the couple continue to live a childless life. Now 17 years later, Mamta is seriously ill, and asks Dinu to bring Sohan back. Dinu goes to the Zamindar's house where he meets a young man who identifies himself as the real son, Suraj, and informs him that Sohan has been asked to leave. A devastated Dinu loses his memory and roams listlessly on the streets of Calcutta, unable to remember anything.
Jeetendra
as Arun / Sohan
Babita Kapoor
as Bharti Gupta
Mehmood
as Chamanlal 'Charlie' Singaporie
Sujit Kumar
as Dr. Mohan
Manmohan Krishna
as Kanta Prasad Gupta
Manmohan
as Suraj / Arun
Achala Sachdev
as Sharda K. Gupta
Sulochana Chatterjee
as Mamta (Dinu's Wife)
Aruna Irani
as Shobha R. Lal
Helen
as Courtesan
Nazir Hussain
as Dinu
Jeevan Dhar
as Munim Ram Lal
