Heeralal's gang now seeks revenge against the family of devout Harnam which comprises his wife, Kaushalya (Kamini Kaushal) and three sons.
Ram Prasad (Rajendra Kumar) grows up to be as a CID Inspector and Laxman Prasad (Shashi Kapoor) as worker in a factory which manufactures Lead Safety Containers for Uranium, for the Government of India, also called Lead shielding; which he also protects from landing in the hands of terrorists who make bombs and thus one of the chief workers, in the good books of the owner (Raj Mehra).
The story then leads to how Laxman Prasad is wrongly framed for the theft of the boxes by Rocky and Badshah and the subsequent murder of Raj Mehra.
Harnam, who has now become a CBI Officer, poses as a sea pirate and joins the gang of Heeralal to transport the uranium in the stolen lead boxes, in a ship.
The movie ends with the family of Harnam Prasad vanquishing the entire gang of smugglers, being true to their legacy of honesty towards their country, and matrimony of the three sons to their love interests.
Rafi, Kishore Kumar, Mukesh, Manhar, Mahendra Kapoor and Anuradha Paudwal, The music was by Laxmikant Pyarelal and Lyrics by Anand Bakshi.