A rich, happy-go-lucky young man lives with his faithful man-servant. The young man gets married to a well-to-do woman who is more educated than him, and she changes him to a more responsible person

Nalla Thanka , the only sister of Nallannan , the King of Madhurapuri, is wedded to Somanathan , the king of the neighbouring kingdom Ratnapuri. Alankari, the wicked wife of Nallannan becomes envious of the prosperity of Ratnapuri and the happy married life of Nalla Thanka.

The story centres around a fisherman Sankaran who loses his wife struggles to bring up his two daughters Nirmala and Vimala. Sankaran’s sister Kalyani looks after the family. Sankaran meets with an accidental death while on a fishing expedition. Nirmala becomes a fish vendor.